JP2008070677A - Exposure apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure apparatus capable of extending a band width without decreasing a drawing resolution. <P>SOLUTION: The exposure apparatus is equipped with: a DMD (exposure unit 30); an imaging optical system 50 having a split reduction projection unit 53 including a cylindrical lens in a first direction that condenses an intermediate projection image comprising the light reflected by micromirrors in an on-state of the DMD to the first direction x as one of the arrangement directions of the intermediate projection image from the DMD, and a cylindrical lens group in a second direction that splits and condenses light in a second direction y as the other direction of the arrangement direction of the intermediate projection image from the DMD, perpendicular to the first direction; and a drawing unit 70 where a projection image is projected form the DMD through the imaging optical system 50 upon exposure, the drawing unit moving in a main scanning direction xx at a predetermined inclination angle θ with respect to the first direction x. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exposure apparatus, and more particularly to an imaging optical system that forms an image of reflected light from a two-dimensional display element such as a DMD (Digital Micromirror Device) on an exposure area.

  Conventionally, an exposure apparatus using a two-dimensional display element such as a DMD has been proposed.

Patent Document 1 discloses an exposure apparatus having a DMD arranged in a state where the arrangement direction of micromirrors is inclined with respect to the main scanning direction on the drawing surface.
JP 2004-12899 A

  However, the drawing area in the apparatus of Patent Document 1 has the same shape as the arrangement of DMD micromirrors. Therefore, in order to increase the resolution, it is necessary to reduce the DMD cell size (micromirror size), but when the cell size is reduced, the cell size is multiplied by the number of cells (the number of arrays in one direction of the micromirror). The bandwidth in the sub-scanning direction based on the obtained value is narrowed. When the band width is narrowed, it is necessary to increase the number of times of exposure (number of bands). When the number of times of exposure is large, a time difference occurs in drawing, and the time difference may cause a thin (non-uniform) drawing line. On the other hand, if the number of cells is increased, the resolution can be increased and the bandwidth can be increased. However, it is necessary to replace the DMD with a large number of cells, and the degree of freedom in design is not high.

  Accordingly, an object of the present invention is to provide an exposure apparatus that can widen the bandwidth without reducing the drawing resolution.

  An exposure apparatus according to the present invention collects an intermediate projection image composed of DMD and light reflected from an on-state micromirror in the DMD in a first direction which is one of the arrangement directions of the intermediate projection images from the DMD. A projection unit having a first direction cylindrical lens that emits light and a second direction cylindrical lens group that divides and collects light in a second direction that is the other of the arrangement directions of the intermediate projection image from the DMD and is perpendicular to the first direction; And an imaging optical system having a drawing unit that projects a projection image from the DMD through the imaging optical system during exposure and moves in a main scanning direction that forms a fixed inclination angle with the first direction.

  Preferably, the fixed inclination angle is one end in the first direction among the specific columns arranged in the first direction in the projection image on the drawing surface of the drawing unit in the ON state from the micromirrors constituting the DMD. A line passing through the section and parallel to the main scanning direction passes through one of the other ends in the first direction of the row arranged in the first direction adjacent to the second direction with respect to the specific row or the vicinity of the other end Set to relationship.

  Preferably, the cylindrical lenses included in the second direction cylindrical lens group are arranged in the second direction by the same number or more as the number of micromirrors constituting the DMD arranged in the second direction.

  Preferably, a plurality of DMDs are arranged in the sub-scanning direction that forms a fixed inclination angle with the second direction.

  More preferably, the bandwidth in the sub-scanning direction of the projection image on the drawing surface of the drawing unit projected from the DMD via the imaging optical system in one projection in exposure is the sub-scanning direction of the region exposed by the DMD. The magnification and shape of the imaging optical system are set so as to be the same as the width.

  An exposure apparatus according to the present invention divides an intermediate projection image composed of DMD and light reflected from an on-state micromirror in the DMD into a first direction which is one of arrangement directions of the intermediate projection images from the DMD. A divided reduction projection unit having a first direction cylindrical lens group to be reduced and a second direction cylindrical lens group to be divided and reduced in a second direction that is the other of the arrangement directions of the intermediate projection image from the DMD and is perpendicular to the first direction And a drawing unit that projects a projection image from the DMD via the imaging optical system during exposure and moves in a main scanning direction that forms a fixed tilt angle with the first direction. The reduction ratio is different between the division reduction in the first cylindrical lens group and the division reduction in the second cylindrical lens group.

  As described above, according to the present invention, it is possible to provide an exposure apparatus that expands the bandwidth without lowering the drawing resolution.

  Hereinafter, the present embodiment will be described with reference to the drawings. The exposure apparatus 1 in this embodiment includes a control unit 10, an exposure unit 30, an imaging optical system 50, a light absorbing plate 60, and a drawing unit 70 (see FIGS. 1 and 2).

  In order to describe the direction, the movement direction of the drawing unit 70 for exposure in the exposure apparatus 1 is the main scanning direction xx, the direction perpendicular to the main scanning direction xx, and the direction in which a plurality of DMDs are arranged (DMD movement direction). In the sub-scanning direction yy, one of the arrangement directions of the images drawn on the drawing unit 70, the direction forming the inclination angle θ with the main scanning direction xx is the first direction x, and the direction perpendicular to the first direction x is the second. In the following description, the direction y, the first direction x, the second direction y, and the direction perpendicular to the drawing surface are defined as a third direction z.

  The control unit 10 performs drawing data processing for creating exposure data (raster data) corresponding to the DMD of the exposure unit 30 based on drawing data (vector data, CAD data) used for exposure.

  The exposure unit 30 has a plurality of DMDs. In this embodiment, each of the plurality of DMDs is described as being configured by arranging 5 × 5 square micromirrors (5 in the first direction x and 5 in the second direction y). The number and shape of the micromirrors included in the are not limited to this (for example, an array of 768 × 1024). The DMD micromirror that is turned on based on the exposure data reflects light incident on the exposure unit 30 and exposes the drawing area of the drawing unit 70 via the imaging optical system 50.

  The tilt angle θ is a main scan that passes through one end of the first direction x in a specific row arranged in the first direction x in the projected image on the drawing surface in the ON state from the micromirrors constituting the DMD. Positional relationship in which a line parallel to the direction xx passes through the other of the first direction x or the vicinity of the other end of the row arranged in the first direction x adjacent to the second direction y with respect to the specific row Set to

  In the present embodiment, the inclination angle θ is one end of the first direction x among the specific columns arranged in the first direction x in the projected image on the drawing surface in the ON state from the micromirrors constituting the DMD. The line parallel to the main scanning direction xx (see the broken line in FIG. 3) passes through the section, and the other of the first direction x of the row arranged in the first direction x adjacent to the second direction y with respect to the specific row It is set to a positional relationship passing through the end.

  The imaging optical system 50 has an enlargement projection unit 51 having a convex lens for enlarging and projecting the reflected light from the DMD micromirror that is turned on, and directs the enlarged projection image (enlarged projection image and intermediate image) to the drawing surface. And a split reduction projection unit 53 that splits and projects the enlarged projection image. The intermediate projection image has a square shape in which five squares are arranged in the first direction x and five squares are arranged in the second direction y (see FIG. 4). Details of the division reduction projection unit 53 will be described later.

  The light absorbing plate 60 absorbs the reflected light from the DMD micromirror that is turned off.

  The drawing unit 70 has a drawing surface. During exposure, the drawing unit 70 is placed in a positional relationship such that the DMD of the exposure unit 30 is turned on and the reflected light of the micromirror is projected (irradiated) onto the drawing area of the drawing surface. The

  At the time of exposure, the drawing unit 70 is moved in the main scanning direction xx so that the relative position between the drawing unit 70 and the exposure unit 30 is changed, and the DMD of the exposure unit 30 is moved in the sub-scanning direction yy.

  Details of the division / reduction projection unit 53 will be described (see FIGS. 3 and 4). The division reduction projection unit 53 includes an aperture 53a, first and second cylindrical lens groups 53b1 and 53b2 as second-direction cylindrical lens groups, and first and second cylindrical lenses 53c1 and 53c2 as first-direction cylindrical lenses. .

  Each part of the division reduction projection unit 53 is directed from the reflector 52 side toward the drawing area side of the drawing unit 70, the aperture 53a, the first cylindrical lens group 53b1, the first cylindrical lens 53c1, the second cylindrical lens 53c2, and the second cylindrical lens. They are arranged in the order of the group 53b2.

  The aperture 53a is composed of a plurality of holes, and light from the reflector 52 is incident on the first cylindrical lens group 53b1 through the plurality of holes. The aperture 53a has an effect (an effect of preventing the occurrence of a ghost) that light from an adjacent lens does not enter.

  The first cylindrical lens group 53b1 has a configuration in which a plurality of cylindrical lenses are arranged in the second direction y. The cylindrical lens has a rectangular shape as viewed from the second direction y, and has an arcuate shape in which the aperture 53a side is an arc portion and the first cylindrical lens 53c1 side is a chord portion as viewed from the first direction x, and forms a shape of a part of a cylinder. That is, the lens ridgeline of the cylindrical lenses constituting the first cylindrical lens group 53b1 is parallel to one of the arrangement directions of the DMD micromirrors (first direction x). The number of the cylindrical lenses arranged in the second direction y is set to be equal to or more than the number of the micromirrors constituting the DMD arranged in the second direction y.

  The first cylindrical lens 53c1 is a single cylindrical lens having a rectangular shape when viewed from the first direction x, an arcuate shape with the first cylindrical lens group 53b1 side being an arc portion and the second cylindrical lens 53c2 side being a string portion when viewed from the second direction y. And forms the shape of a portion of a cylinder.

  The second cylindrical lens 53c2 is a single cylindrical lens having a rectangular shape when viewed from the first direction x, an arcuate shape with the first cylindrical lens 53c1 side being a chord portion and the second cylindrical lens group 53b2 side being an arc portion when viewed from the second direction y. And forms the shape of a portion of a cylinder.

  The second cylindrical lens group 53b2 has a configuration in which a plurality of cylindrical lenses are arranged in the second direction y. The cylindrical lens has a rectangular shape as viewed from the second direction y, and has an arcuate shape in which the second cylindrical lens 53c2 side is a chord portion and the drawing surface side is an arc portion when viewed from the first direction x, and forms a part of a cylindrical shape. That is, the lens ridge line of the cylindrical lenses constituting the second cylindrical lens group 53b2 is parallel to one of the arrangement directions of the DMD micromirrors (first direction x). The number of the cylindrical lenses arranged in the second direction y is set to be equal to or more than the number of the micromirrors constituting the DMD arranged in the second direction y.

  In each of the cylindrical lenses constituting the first and second cylindrical lens groups 53b1 and 53b2, the light reflected from the on-state mirror in the DMD and passing through the aperture 53a is divided and condensed in the second direction y. (The light is not condensed in the first direction x).

  In each of the first and second cylindrical lenses 53c1 and 53c2, the light reflected from the on-state mirror in the DMD and passing through the aperture 53a is condensed in the first direction x (in the second direction y). Is not collected).

  The intermediate image obtained by enlarging the image (irradiation image) irradiated by the exposure unit 30 by the division projection unit 53 by the division projection unit 51 is reduced in the first direction x, divided and reduced in the second direction y, and drawn. The projected image in the drawing area of the unit 70 forms an image in which five rectangles arranged with five squares in contact with the first direction x are arranged in the second direction y at regular intervals.

  In the projected image, the arrangement direction (first direction x) in a state where the squares are in contact forms an inclination angle θ with respect to the main scanning direction xx, and the arrangement direction of the rectangles in which the squares are arranged (second direction y). The tilt angle θ is formed with respect to the sub-scanning direction yy.

  In this embodiment, the squares (rectangles in which the squares are arranged in the first direction x) are arranged in the second direction y in a state where the intervals are widened. Therefore, the squares (squares in the first direction x) are arranged. The size (bandwidth) of the projected image in the second direction y can be made larger than when the same number of arranged rectangles) are arranged in the second direction y without expanding the interval. . By widening the bandwidth, the number of times of exposure (number of bands × number of DMD arrays) can be reduced. If the number of bands is large, there will be a difference in drawing time, which may cause the drawing lines to be thick and thin (uneven thickness, line width difference). It becomes possible to reduce.

  Further, the squares forming the projection image (rectangles in which the squares are arranged in the first direction x) are arranged in the second direction y with the interval being widened, and the main scanning direction xx and the sub-scanning direction yy are projected. Since the inclination angle θ is formed with respect to the direction in which the squares of the image are arranged (the first direction x and the second direction y), it is possible to increase the drawing resolution while increasing the bandwidth. become.

  In addition, since the squares constituting the projection image are arranged in the first direction x without expanding the interval, the size of the projection image is smaller than that in the case where the projection image is arranged in the first direction x with the interval expanded. Tesumu. Therefore, the amount of exposure data corresponding to the projection image can be smaller than that in the case where the exposure data is arranged in the first direction x with the interval widened, and there is an advantage that the processing speed can be increased.

  In addition, since a cylindrical lens is used as an imaging optical system for projecting a projection image, the position adjustment is only required in one direction compared to a configuration in which microlenses are arranged in a two-dimensional direction. .

  Further, the interval in which the squares constituting the projection image (rectangles in which the squares are arranged in the first direction x) are arranged in the second direction y is widened, and the bandwidth of the projection image in the sub-scanning direction yy is one DMD. By setting the magnification and shape of the imaging optical system 50 (particularly, the first and second cylindrical lens groups 53b1 and 53b2) so as to be the same as the width of the exposure area in the sub-scanning direction yy, the DMD is sub-scanned. It is possible to perform exposure without moving in the direction yy.

  In addition, the first and second cylindrical lenses 53c1 and 53c2 are also divided so that the squares arranged in the first direction x are arranged in a wide interval as a cylindrical lens group constituted by a plurality of cylindrical lenses. It may be in the form of reduction (only reduction in the case of a single cylindrical lens). In this case, the reduction ratio divided and reduced in the first direction x by the cylindrical lens group constituted by a plurality of cylindrical lenses instead of the first and second cylindrical lenses 53c1 and 53c2 is the first and second cylindrical lens groups 53b1, The shape and magnification are set so as to be different from the reduction ratio divided and reduced in the second direction y by 53b2.

It is a perspective view which shows the exposure apparatus in this embodiment. It is a perspective view which shows the structure of an exposure part, an imaging optical system, and a drawing part. It is a perspective view which shows the structure of the division | segmentation reduction projection part of an imaging optical system, and a drawing part. It is a side view which shows the structure of an exposure part and an imaging optical system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 10 Control part 30 Exposure part 50 Imaging optical system 51 Enlargement projection part 52 Reflector 53 Division reduction projection part 53a Aperture 53b1, 53b2 1st, 2nd cylindrical lens group 53c1, 53c2 1st, 2nd cylindrical lens 60 Light Absorbing plate 70 Drawing part

Claims (6)

DMD,
A first direction cylindrical lens that condenses an intermediate projection image composed of light reflected from an on-state micromirror in the DMD in a first direction that is one of the arrangement directions of the intermediate projection image from the DMD; An imaging optical system having a projection unit having a second direction cylindrical lens group that divides and condenses in a second direction that is the other of the arrangement directions of the intermediate projection image from the DMD and is perpendicular to the first direction;
An exposure apparatus comprising: a drawing unit that projects a projection image from the DMD through the imaging optical system during exposure and moves in a main scanning direction that forms a fixed inclination angle with the first direction.   The fixed inclination angle is one of the first directions in the specific row arranged in the first direction in the projection image on the drawing surface of the drawing unit in the ON state from the micromirrors constituting the DMD. The line parallel to the main scanning direction passing through the end of the first one of the rows in the first direction adjacent to the second direction with respect to the specific row or the other in the first direction The exposure apparatus according to claim 1, wherein the exposure apparatus is set in a positional relationship passing through the vicinity of the end of the exposure apparatus.   2. The cylindrical lenses included in the second-direction cylindrical lens group are arranged in the second direction by the same number or more as the number of micromirrors constituting the DMD arranged in the second direction. The exposure apparatus described in 1.   2. The exposure apparatus according to claim 1, wherein a plurality of the DMDs are arranged in a sub-scanning direction that forms the constant inclination angle with the second direction.   The bandwidth in the sub-scanning direction of the projected image on the drawing surface of the drawing unit projected from the DMD via the imaging optical system by one projection in the exposure is the sub-width of the region exposed by the DMD. 5. The exposure apparatus according to claim 4, wherein the magnification and shape of the imaging optical system are set so as to be the same as the width in the scanning direction. DMD,
A first-direction cylindrical lens group that divides and reduces an intermediate projection image composed of light reflected from an on-state micromirror in the DMD in a first direction that is one of the arrangement directions of the intermediate projection image from the DMD; An imaging optical system having a division reduction projection unit having a second direction cylindrical lens group which is the other of the arrangement directions of the intermediate projection images from the DMD and which is divided and reduced in a second direction perpendicular to the first direction; ,
A projection unit that projects a projection image from the DMD through the imaging optical system during exposure and moves in a main scanning direction that forms a fixed inclination angle with the first direction;
An exposure apparatus, wherein the reduction ratio is different between the division reduction in the first cylindrical lens group and the division reduction in the second cylindrical lens group.

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