JP2009288301A - Proximity exposure apparatus - Google Patents

Abstract

An object of the present invention is to provide a proximity exposure apparatus capable of accurately aligning a substrate and an exposure mask at low cost.
SOLUTION: Conveying means 4 for placing and conveying a workpiece W to be exposed, an exposure mask 31 in close proximity to the workpiece W, an alignment mark WB on the workpiece W, and an alignment mark 31d on the exposure mask 31 The image pickup means 5 for picking up the images at the same time, and exposure is performed while aligning the workpiece W and the exposure mask 31 based on the respective images of the alignment mark WB and the alignment mark 31d picked up by the image pickup means 5. A proximity exposure apparatus, which is disposed between the imaging means 5 and the workpiece W or the exposure mask 31, and the optical distance (L1 or L2) between the imaging means 5 and the workpiece W or the exposure mask 31 is discontinuous. And an optical distance correcting means 52 having an optical member 52a that is variable.
[Selection] Figure 6

Description

  The present invention relates to a proximity exposure apparatus that images each alignment mark of a substrate to be exposed and an exposure mask, and aligns and exposes the substrate and the exposure mask based on those images. The present invention relates to an exposure apparatus in which the alignment marks of the substrate and the exposure mask are simultaneously formed on the light receiving surface of the image pickup means to perform the alignment process at high speed.

A conventional exposure apparatus is formed on a stage on which a substrate to be exposed is placed, a mask stage that holds an exposure mask in close proximity to the substrate, a substrate-side alignment mark formed on the substrate, and the exposure mask. Imaging means that captures and captures each mask-side alignment mark in the same field of view. First, the imaging means is moved while the mask-side alignment mark is imaged on the light-receiving surface of the imaging means. Position the mask side alignment mark at the center, then move the stage with the substrate side alignment mark imaged on the light receiving surface and position the substrate side alignment mark at the center in the field of view of the imaging means. One that performs alignment with an exposure mask is known (see, for example, Patent Document 1).

In addition to the above, a transparent member (optical path length correcting means) having a predetermined refractive index disposed on the optical path connecting the light receiving surface of the image pickup means and the substrate is provided, and the light receiving surface of the image pickup means and the substrate And the optical distance between the light receiving surface of the image pickup means and the exposure mask are substantially matched, and the image pickup means captures the substrate side and mask side alignment marks in the same field of view and takes an image. There is also known a system in which the image processing of the substrate side alignment mark and the mask side alignment mark is performed at the same time, and the alignment processing of the substrate and the exposure mask is performed (for example, see Patent Document 2).
As the optical path length correcting means, in addition to the fixed type as in the above-mentioned Patent Document 2, there are known two types of prisms each having a wedge angle so that the optical path length can be freely changed ( For example, see Patent Document 3).
Japanese Patent Laid-Open No. 5-196420 JP 2007-102094 A JP 2007-86372 A

However, in such a conventional exposure apparatus (the former), since the optical path lengths of the substrate side alignment mark and the mask side alignment mark from the imaging unit are different, the mask side alignment mark is imaged on the light receiving surface of the imaging unit. Therefore, it is necessary to move the imaging means in the direction of the optical axis and to form an image of the substrate side alignment mark on the light receiving surface, which increases the alignment processing time.

Further, in the conventional exposure apparatus (the latter), since the optical path length correction means cannot freely correct the optical path length, each time the gap between the substrate and the exposure mask is changed, the optical path length correction means is set to the optimum thickness. It was necessary to replace it with something, and the work was difficult.
Further, if the optical path length correcting means is of the type as described in Patent Document 3, it is easy to cope with the change in the gap between the substrate and the exposure mask. However, the optical path length correcting means as in Patent Document 3 is used. In this case, since the structure is complicated and the mounting space becomes large, it is difficult to arrange between the light receiving surface of the image pickup means and the exposure mask, and it is necessary to make the wedge angles of the two prisms the same. Therefore, there is a problem that the manufacturing cost of the prism is increased.
Furthermore, since light is transmitted through the two prisms, there is a problem in that the optical axis shifts when the prism is deformed due to changes in the ambient temperature of each prism.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a proximity exposure apparatus that can cope with such problems and can accurately align a substrate and an exposure mask at low cost.

In order to achieve the above object, an invention according to claim 1 includes a stage on which a substrate to be exposed is placed, and a mask that is disposed above the stage and holds an exposure mask in close proximity to the substrate. A stage, an imaging means for simultaneously imaging a reference location on the substrate and a reference location on the exposure mask, and a reference location on the substrate imaged by the imaging means; and A proximity exposure apparatus that moves the stage and the mask stage relative to each other based on respective images of a reference location on an exposure mask, aligns the substrate and the exposure mask, and performs exposure. An optical distance correction unit is provided between the light receiving surface of the imaging unit and the substrate, and has an optical member that discontinuously varies the optical distance between the light receiving surface of the imaging unit and the exposure mask. It is characterized in that.

According to a second aspect of the present invention, in the first aspect, the optical member is an optical member having a plurality of planes parallel to a plane perpendicular to the optical axis of the imaging means in a step shape.

According to a third aspect of the present invention, in the first or second aspect, the optical member has a plurality of planes arranged in a row in parallel with the reference plane on the reference plane. It is said.

According to a fourth aspect of the present invention, in the first to third aspect of the present invention, the optical member is a hexahedron in which opposing faces are parallel and the angle formed between adjacent faces is a right angle. It is characterized by that.

According to the present invention, even when the substrate and the exposure mask are arranged so as to be shifted from each other in the optical axis direction of the imaging means, the reference position on the substrate and the reference position on the exposure mask are determined by the imaging means. Images can be simultaneously formed on the light receiving surface.
Therefore, image processing of the image of the reference location on the imaged substrate and the reference location on the exposure mask can be performed in real time, and the alignment processing of the substrate and the exposure mask can be performed at high speed. . Further, unlike the prior art, the image pickup means is not moved in the optical axis direction to pick up images of the substrate side and exposure mask side alignment marks, respectively, so that there is no position shift due to movement shift of the image pickup means. Therefore, the alignment accuracy can be improved.

Further, since the optical member of the optical path length correcting means has a plurality of stepped parallel planes (that is, a plurality of flat plates having different thicknesses), a prism having a wedge angle even if it is deformed by heat. There is little worry about the optical axis misalignment.
In addition, since the optical member has the above configuration, the structure of the optical path length correction means can be made simple and compact, and since it has a plurality of planes parallel to each other, when the gap between the exposure mask and the substrate is changed, A portion having a thickness in the optical axis direction that matches the gap can be easily selected.
Furthermore, the production cost of the optical member can be reduced.

Furthermore, since the optical member has a plurality of planes arranged in a row in parallel with the reference plane, the reference plane can be used as an assembly reference for the optical distance correction means. The optical distance correction means can be easily assembled.
Furthermore, since the optical member is composed of the plurality of independent hexahedrons, the optical member can be easily manufactured, and the influence of thermal expansion of adjacent optical members can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a conceptual diagram showing a proximity exposure apparatus 1 according to a first embodiment of the present invention.
The proximity exposure apparatus 1 includes an exposure light source unit 2, an exposure mask unit 3, a work transfer device 4 that transfers an exposure target substrate, an imaging unit 5, an illumination light source 6, and a control device that controls these (see FIG. (Not shown).
In the following description, the case where the substrate to be exposed is a color filter substrate (hereinafter simply referred to as “work W”) (FIG. 9) coated with a color resist as a photosensitive resin described later will be described.

The exposure light source unit 2 is a light source 2a (for example, an ultra-high pressure mercury lamp, a xenon lamp or an ultraviolet light emitting laser) that emits exposure light (ultraviolet light) and a light beam emitted from the light source 2a into a bundle of predetermined parallel lights. The optical system 2b is disposed above the exposure mask unit 3, and the optical system 2b faces an exposure mask 31 described later. The light source 11a is connected to the control device via a light source controller (not shown).
The illumination light source 6 irradiates parallel white light to the exposure mask 31 side.

As shown in FIG. 2, the exposure mask unit 3 includes a mask holder 30, at least one exposure mask 31 mounted on the mask holder 30, and the mask holder 30 as an X axis, Y axis, Z axis, θ axis, α Mask holder driving means (not shown) for controlling the position and orientation of each axis.
The mask holder 30 holds the exposure mask 31 in a state in which the exposure mask 31 is closely opposed to the workpiece W with a predetermined gap (for example, 100 to 300 μm).

As shown in FIG. 3, the exposure mask 31 includes a transparent substrate 31a (for example, quartz glass) that transmits ultraviolet light and visible light with high efficiency, and a light-shielding film 31b that is applied to the transparent substrate 31a and shields exposure light. It is composed of a plurality of mask patterns 31c that are openings of a predetermined shape that are formed on the light shielding film 31b and allow exposure light to pass through, a mask side viewing window 31e, and a mask side alignment mark 31d.
A wavelength-selective film (not shown) that allows white light to pass through and blocks ultraviolet light is applied to the surface of the mask-side viewing window 31e.
Thus, the exposure light irradiated to the exposure mask 31 is reflected by the light shielding film 31b and does not irradiate the workpiece W through the surface other than the mask pattern 31c.
The exposure mask 31 is set in the mask holder 30 so that the mask side observation window 31e is on the upstream side in the conveyance direction A of the workpiece W (below the paper surface in FIG. 3A).

The mask pattern 31c has a width (Mb) substantially coincident with a width WPb (FIG. 10) of a pixel WP of the work W, which will be described later, and has a long rectangular shape in the direction of the arrow A, and a direction orthogonal to the arrow A. In parallel with each other, the pixel WP is formed at an interval that coincides with an interval of 3 pitches (Py).
As shown in FIG. 3, for example, an edge S1 (FIG. 3a) in the Y-axis direction of the mask pattern 31c located at the center is set in advance as a reference position.
The mask-side alignment mark 31d is made of a material that blocks both white light and ultraviolet light in the mask-side viewing window 31e, and the edge S2 (FIG. 3a) of the mask-side alignment mark 31d in the Y-axis direction is the mask pattern. It is drawn so as to coincide with the edge S1 of 31c.

The work transfer device 4 is disposed below the exposure mask unit 2 and includes a stage 40 and a work transfer means (not shown).
The stage 40 has a large number of ejection holes (not shown) for ejecting gas and a number of suction ports for sucking gas on the upper surface, and is connected to a compressed gas supply device and a gas suction device (not shown) to eject gas. The workpiece W is floated on the stage 40 due to the balance of suction, and a portion facing the exposure mask 31 is opened, and the opening portion 41 has a front side of the exposure position by the exposure mask 31. The image pickup means 5 for picking up an image of the workpiece W from the lower side is provided toward the workpiece W at the position (right side as viewed in FIG. 1).

The workpiece transfer means can transfer the workpiece W on the stage 40 in the direction of the arrow A in a state where a part of the workpiece W (one of the edges parallel to the transfer direction of the workpiece W) is held by a holding means (not shown). Furthermore, a work position sensor (not shown) for detecting the position of the work W in the direction of the arrow A is further provided.

Further, the image pickup means 5 is provided in the opening 41 below the mask side viewing window 31e of the exposure mask 31 (FIG. 4), facing the lower surface of the work W, and as shown in FIG. A line sensor 50 including a plurality of imaging elements 50a arranged in a line perpendicular to the direction, a lens system 51 having a predetermined depth of focus, provided between the line sensor 50 and the workpiece W, and a lens system 51. An optical path length correcting means 52 is provided between the line sensor 50 and the optical sensor.

As shown in FIG. 7, the optical path length correcting means 52 includes an optical member 52a (FIG. 8) having different thicknesses in stages, and an optical for moving the optical member 52a forward and backward in the arrow B direction (FIG. 6) parallel to the X-axis direction. A member driving device 52b is provided.
The optical member driving device 52b includes a holder 52b1 that holds the optical member 52a, a pair of guides 52b2 and 52b2 that support two opposing sides of the holder 52b1 and are movable in the direction of the arrow B, A ball screw (not shown) provided along the guide 52b2, a ball nut (not shown) fitted to the ball screw and attached to the holder 52b1, and one end of the ball screw. A driving motor 52b3 for rotating the screw and a rotary encoder (not shown) attached to the driving motor 52b3 are provided.

The drive motor 52b3 is connected to the control device via a motor controller (not shown), and the rotary encoder is connected to the control device.
The line sensor 50 is arranged such that a predetermined light receiving element 50a in the group of light receiving elements 50a constituting the line sensor 50 corresponds to the edge S2 of the mask side alignment mark 31d of the exposure mask 31. Yes.

The optical member 52a is made of a homogeneous transparent material, and has a reference surface 52a1 and a plurality of step-like planes parallel to the reference surface 52a1, as shown in FIG.
The thicknesses of the plurality of stepped planes (hereinafter simply referred to as “stepped portions”) (52a2 to 52a7) from the reference plane 52a1 are t1 to t6, respectively.
Note that the optical member 52a is not limited to the shape shown in FIG. 8, and may have a shape shown in FIGS.
The optical member (52A) in FIG. 13 is made of a plurality of plate-like homogeneous transparent materials with different thicknesses arranged in a line on the reference plane (52A1), and the temperature of the optical member 52A changes. Even so, each optical member (52A2 to 52A7) is not easily affected by the thermal expansion of adjacent optical members.
Since the optical member (52B) in FIG. 14 has a target structure in the vertical direction of the paper surface in FIG. 14, even if the temperature of the optical member (52B) changes, the optical member 52B is unlikely to warp, and the optical path There is a feature that is difficult to cause the deviation.
The optical member (52C) of FIG. 15 is obtained by replacing the stepped portions 52B1 to 52B7 of the optical member 52B of FIG. 15 with independent members 52C1 to 52C7, and has an advantage that the optical member 52C can be easily manufactured.
The optical member (52D) in FIG. 16 is obtained by changing the arrangement of the respective parts (52A2 to 52A7) in FIG. 13. By arranging the respective parts (52A2 to 52A7) in the order of use frequency, the operation of the holder 52b1 is performed. There is a feature that can be simplified.
In addition to the optical member, portions corresponding to the respective portions (52A2 to 52A7) of the optical member 52D in FIG. 16 may be integrally formed.

The thicknesses t1 to t6 vary depending on the magnification of the lens system 51, the depth of focus, the required optical path length difference, and the material of the optical member 52a. For example, the magnification of the lens system 51 is 5 times and the material of the optical member 52a. In the case where the refractive index is 1.5168, the depth of focus is ± 20 μm, and the required optical path length difference is in the range of 150 μm to 350 μm, and the correction of this optical path length difference is set in units of 1 μm, t1 to t6 are These are 7.3 mm, 9.4 mm, 11.6 mm, 13.7 mm, 15.8 mm, and 18 mm, respectively.
The optical path length difference is obtained by the following equation.
Optical path length difference = T × (N−1) / (N × M ² )
Where T: optical member thickness, N: optical member refractive index, M: lens system magnification

That is, when the focal depth of the lens system is ± 20 μm, it is possible to image up to an optical path length difference of ± 20 μm with one plane portion, but when the optical path length difference is more than that, a step portion with the next thickness is provided. The optical path length is corrected by moving on the optical axis of the image sensor 50a.
Therefore, when the focal position of the lens system is made to coincide with the surface of the planar portion of each optical member, the optical path length adjustable range of the planar portion (from t1 to t6) of each optical member is 117 to 157 μm, 157 to 197 μm, 197 to 237 μm, 237 to 277 μm, 277 to 317 μm, and 317 to 357 μm.

The imaging means 5 can capture and image a substrate-side alignment mark WB formed on the workpiece W, which will be described later, and a mask-side alignment mark 31d formed on the exposure mask 31, respectively, in the same field of view. It is.
That is, as shown in FIG. 4, in a state where the imaging means 5 images the substrate side alignment mark WB of the workpiece W (a state where the condensing point F coincides with the line sensor 50), the imaging means 5 The light a emitted from the mask-side alignment mark 31d of the exposure mask 31 whose optical distance from the lens system 51 is farther than the substrate-side alignment mark WB of the workpiece W forms an image on the front side of the image sensor 50a as it is. However, by passing through the optical member 52a of the optical path length correcting means 52, the optical path length becomes longer, and the light beam can be condensed on the line sensor 50. Thereby, the mask side alignment mark 31d and the substrate side alignment mark WB can be simultaneously imaged on the line sensor 50.

Next, the exposure operation of the proximity exposure apparatus 1 configured as described above will be described with reference to the accompanying drawings.
Here, as shown in FIG. 9, an opaque film made of Cr or the like is formed on one surface of a transparent glass substrate, and a plurality of pixels WP are arranged in a matrix in an exposure region on the opaque film. An ultraviolet curable color resist (red, blue, green) is applied to the formed surface.
In the non-exposure area, a substrate side observation window WW on which an opaque film is not formed, and a substrate side alignment mark WB drawn by a material that blocks both white light and ultraviolet light in the substrate side observation window WW, , And the substrate side alignment mark WB is provided at a position that coincides with the edge S4 of the predetermined pixel WPK1, as shown in FIG.

First, as an initial preparation, the lens system 51 of the imaging unit 5 is set so that an image of the pixel WP of the workpiece W is formed on the imaging unit 5. In this case, it is preferable that an image of the pixel WP of the workpiece W is formed on the line sensor 50 at a substantially central position of the focal depth of the lens system 51.
Next, based on the difference in the optical distance (L1, L2) from the imaging means 5 of the workpiece W and the exposure mask 31, the thickness portion (for example, the optical member 52a) that is suitable for correcting the difference in the optical distance. 52a3) is positioned on the optical axis of a region of a predetermined image sensor 50a that performs imaging of the mask side alignment mark 31d of the line sensor 50 by operating the driving motor 52b3 of the optical member driving device 52b.
As a result, the substrate side alignment mark WB of the workpiece W and the mask side alignment mark 31d of the exposure mask 31 can be imaged on the line sensor 50 simultaneously.

Next, the workpiece W is continuously conveyed in the direction of arrow A by the workpiece conveying means, with the workpiece side observation window WW first. Then, when the workpiece W passes over the imaging unit 5, the imaging unit 5 simultaneously images the substrate-side alignment mark WB and the mask-side alignment mark 31 d of the workpiece W by the imaging unit 5.

Thereafter, the images of the substrate-side alignment mark WB and the mask-side alignment mark 31d of the workpiece W that are simultaneously captured are simultaneously processed by an image processing unit (not shown).
At this time, the edge S5 of the substrate side alignment mark WB of the workpiece W is detected, and the cell number of the light receiving element 50a of the line sensor 50 detected and the light reception of the line sensor 50 detecting the edge S2 of the mask side alignment mark 31d of the exposure mask 31. The cell number of the element 50a is read, and the distance Lx is calculated. Then, it is compared with a predetermined distance L0 set and stored in advance.

When the workpiece W is displaced in the Y-axis direction with respect to the exposure mask 31 (distance Lx ≠ L0 ± α (α is an allowable value)), the distance Lx is set to L0 or L0 ± by the mask holder driving unit. The exposure mask 31 is moved in the Y-axis direction so that α (α is an allowable value). As a result, the distance Lx between the mask-side alignment mark 31d of the exposure mask 31 and the substrate-side alignment mark WB of the workpiece W matches within a predetermined allowable range.
Note that the state within the predetermined allowable range (distance Lx = L0 ± α) is also a state in which each mask pattern 31d is transferred onto each pixel WP without deviation by exposure light.

If the distance Lx matches within a predetermined allowable range, it is determined that the alignment has been performed reliably, and the exposure mask 31 is irradiated with exposure light. Thereby, the image of the mask pattern 31d of the exposure mask 31 is transferred onto the pixel WP of the workpiece W. If the distance Lx is not within a predetermined allowable range, for example, it is determined that the workpiece W is of a different type, or an opaque film formation product of the workpiece W. In this case, the exposure is stopped and an alarm is issued. Is issued.

Thereafter, along with the continuous conveyance of the work W, the edge S3 of the reference pixel WPK2 set in advance and the respective edges of the pixels WP aligned in the X-axis direction of the reference pixel WPK2 (on the extension line of the edge S3 of the pixel WPK2) If the cell number of the image sensor 50a of the line sensor 50 that continuously captures the edge of the image sensor is different from the initial state (the state where the Lx is set within L0 ± α), the cell number of each image sensor 50a. From the above, in the control device, the distance (deviation amount) of the workpiece W in the Y-axis direction is calculated.

Then, a signal is sent from the control device to the mask holder driving means based on the amount of deviation, and the mask holder 30 is moved in the Y-axis direction so that each edge of the pixel WP (the edge S3 of the pixel WPK2). The cell number of the image sensor 50a that captures the edge of the extended line in the X-axis direction is always maintained at the initial cell number.
Thereby, even if the workpiece W is conveyed while swinging in a direction orthogonal to the conveyance direction indicated by the arrow A, the exposure mask 31 is moved following the movement, and an image of the mask pattern 31c of the exposure mask 31 is formed at the target position. It will be transferred with high accuracy.

In the above embodiment, the case where the substrate-side alignment mark WB is formed on the workpiece W has been described. However, the present invention is not limited to this, and the substrate-side alignment mark WB may be omitted. In this case, the result of detecting the edge S4 of the reference pixel WPK1 by the imaging means 5 may be used for detecting the Lx instead of the edge S5 of the substrate side alignment mark WB.

Next, FIG. 11 is a conceptual view showing the proximity exposure apparatus 100 according to the second embodiment of the present invention.
In addition, the same number is attached | subjected about the proximity exposure apparatus 100 which concerns on this Embodiment, and each component apparatus same as the proximity exposure apparatus 1. FIG.
The proximity exposure apparatus 100 includes an exposure light source unit 2, an exposure mask unit 3, a work transport device 4 that transports an exposure target substrate, an imaging unit 5, an illumination light source 6, an exposure mask unit 3, and an imaging unit 5. And a control device (not shown) for controlling them.

The imaging means 5 in the proximity exposure apparatus 100 is disposed above the exposure mask unit 3, and its optical axis is in a direction perpendicular to the optical axis of the exposure light.
The other components of the proximity exposure apparatus 1 and the proximity exposure apparatus 100 are the same.
Therefore, the above differences will be mainly described below. The case where the exposure target substrate of the proximity exposure apparatus 100 is the same as the workpiece W will be described.

The half mirror 6b is disposed with the reflecting surface facing the lower side of the paper surface of FIG. 11 at an angle of approximately 45 degrees with respect to the optical axis of the imaging means 5.
The half mirror 6b transmits the white light from the illumination light source 6 and irradiates the exposure mask 31 with the white light, and also irradiates the workpiece W through the mask side observation window 31e of the exposure mask 31. At the same time, the white light reflected from the workpiece W is directed to the imaging means 5.

Further, as shown in FIG. 12, the optical path length correcting means 52 includes a substrate-side alignment mark 31d so that the mask-side alignment mark 31d and the substrate-side alignment mark WB are imaged simultaneously. It is arranged on the optical path between the mark WB and the imaging means 5. (In the present embodiment, the workpiece W is longer in optical distance from the imaging means 5 than the exposure mask 31.)
FIG. 12 shows an optical positional relationship among the optical path length correcting means 52, the workpiece W, and the exposure mask 31, and the half mirror 6b is omitted.

In the proximity exposure apparatus 100, the selection and exposure operation of each thickness portion (52a2 to 52a7) of the optical member 52a of the optical path length correction means 52 are performed in the same manner as the proximity exposure apparatus 1 described above.
In the exposure operation of the proximity exposure apparatus 100, the lens system 51 of the imaging unit 5 is set so that the mask-side alignment mark 31d of the exposure mask 31 is imaged on the imaging unit 5 as an initial preparation. In this case, it is preferable that the mask-side alignment mark 31d is imaged on the imaging means 5 at a substantially central position of the focal depth of the lens system 51.

Next, based on the difference between the optical distances (L1, L2) from the image pickup means 5 between the workpiece W and the exposure mask 31, the thickness portion of the optical member 52a (corresponding to correcting the difference in optical distance) ( For example, 52a3) is positioned on the optical axis of a region of a predetermined image sensor 50a that images the substrate side alignment mark WB of the line sensor 50 by operating the driving motor 52b3 of the optical member driving device 52b.
As a result, the substrate side alignment mark WB of the workpiece W and the mask side alignment mark 31d of the exposure mask 31 can be imaged on the line sensor 50 simultaneously.
Since the subsequent exposure operation is the same as that of the proximity exposure apparatus 1, description thereof is omitted.

In the above description, the case where the workpiece W is continuously conveyed in a predetermined direction (arrow A) during the exposure operation has been described. However, the present invention is not limited to this. The exposure pattern 31c may be subjected to step exposure.

In the above description, the case where the workpiece W is a color filter substrate has been described. However, the present invention is not limited to this, and any semiconductor substrate or the like may be used as long as it forms a predetermined exposure pattern.

It is a front view which shows schematic structure of 1st Embodiment of the proximity exposure apparatus by this invention. It is a schematic perspective view which shows one structural example of the mask holder used in the said exposure apparatus. It is the schematic for demonstrating the exposure mask used in the said exposure apparatus, Comprising: (a) is a top view, (b) is a perspective view. It is a conceptual diagram for demonstrating the imaging means used in the said exposure apparatus. It is explanatory drawing which shows the principle of the optical distance correction | amendment used in the said exposure apparatus. It is explanatory drawing for demonstrating the motion of the optical member used in the said exposure apparatus. It is a conceptual diagram of the optical distance correction | amendment means used in the said exposure apparatus. It is explanatory drawing explaining the optical member of the optical distance correction | amendment means used in the said exposure apparatus. It is explanatory drawing for demonstrating the workpiece | work supplied in the said exposure apparatus. It is a conceptual diagram for demonstrating the relationship between the workpiece | work in the said exposure apparatus, an exposure mask, and an imaging means. It is a front view which shows schematic structure of 2nd Embodiment of the proximity exposure apparatus by this invention. It is explanatory drawing which shows the principle of the optical distance correction | amendment used in the exposure apparatus of 2nd Embodiment. It is a conceptual diagram for demonstrating the other example of the optical member used for the proximity exposure apparatus by this invention. It is a conceptual diagram for demonstrating the other example of the optical member used for the proximity exposure apparatus by this invention. It is a conceptual diagram for demonstrating the other example of the optical member used for the proximity exposure apparatus by this invention. It is a conceptual diagram for demonstrating the other example of the optical member used for the proximity exposure apparatus by this invention.

Explanation of symbols

1: Proximity exposure device 2 of the first embodiment: Exposure light source unit 2a: Exposure light source 2b: Optical system 3: Exposure mask unit 4: Work transfer device 5: Imaging means 6: Illumination unit 6a: Illumination light source 7 : Deflection mirror 30: Mask holder 31: Exposure mask 31 d: Mask side alignment mark 31 e: Mask side viewing window 40: Stage 50: Line sensor 50 a: Light receiving element 51: Lens system 52: Optical path length correction means 52 a, 52 A, 52 B, 52C, 52D, 52E: Optical member W: Workpiece WB: Substrate side alignment mark WP: Pixel

Claims (4)

A stage on which the substrate to be exposed is placed; a mask stage which is disposed above the stage and holds the exposure mask in close proximity to the substrate; a reference position on the substrate; and the exposure mask And an image pickup means for simultaneously picking up an image of the reference location on the substrate and the reference location on the exposure mask based on the respective images of the reference location on the exposure mask. A proximity exposure apparatus that relatively moves a stage and a mask stage, aligns the substrate and an exposure mask, and performs exposure.
An optical distance correction unit having an optical member which is disposed between the light receiving surface of the image pickup unit and the substrate and discontinuously varies the optical distance between the light receiving surface of the image pickup unit and the exposure mask; A proximity exposure apparatus comprising: 3. The proximity exposure apparatus according to claim 1, wherein the optical member has a plurality of step-like planes parallel to a plane perpendicular to the optical axis of the imaging means. 4. The proximity exposure apparatus according to claim 1, wherein the optical member has a plurality of planes arranged in a row in parallel with the reference plane on the reference plane. 5. 5. The optical member according to claim 1, wherein opposing surfaces are hexahedrons parallel to each other, and an angle formed by adjacent surfaces is a right angle. 6. Proximity exposure equipment.