JP2006098650A - Exposure apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure apparatus in which exposure of a mask pattern can be fast performed with high accuracy while preventing misalignment of exposure caused by expansion/contraction of an object substrate to be exposed or of a mask on exposing the object substrate. <P>SOLUTION: The exposure apparatus 10 comprises: an object substrate 11 to be exposed which is coated with a photosensitive material; a mask 12 having a predetermined mask pattern formed thereon; a light source device 13 to project the mask pattern onto the object substrate 11 to expose; a positioning means 14 to position the object substrate 11 and the mask 12 opposing to each other at a predetermined spacing; an exposure magnification controlling means 15 to control the exposure magnification of the mask pattern projected onto the substrate 11; and a controlling means 16 to control the exposure magnification controlling means 15, based on results of magnification correction operation using a preliminarily determined relational expression. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus and an exposure method.

  2. Description of the Related Art Conventionally, in an exposure apparatus used for manufacturing an IC or the like, a substrate to be exposed is exposed by irradiating light onto a substrate to be exposed (workpiece) coated with a photosensitive agent through a photomask having a mask pattern formed thereon. A method of transferring a mask pattern on top is employed. For exposure, a contact exposure method in which parallel light is irradiated with the substrate to be exposed and the photomask in close contact with each other, and parallel light is irradiated with a slight space between the substrate to be exposed and the photomask. There is a proximity exposure method. In particular, the proximity exposure method has an advantage that the photomask is less likely to get dirty and has a longer life than the contact exposure method because the photomask and the substrate to be exposed do not come into contact with each other.

  FIG. 5 is a schematic view of a conventional exposure apparatus. The exposure apparatus 70 is a proximity exposure type exposure apparatus, and a substrate 72 to which an exposed substrate (hereinafter referred to as “substrate”) 71 coated with a photosensitive agent and a loaded substrate 71 are fixed by vacuum suction. An XYθ driving unit 73 that drives the base 72 in the XY direction and θ (rotation) direction, a mask 74 having a predetermined mask pattern formed between the substrate 71 and a predetermined distance, and a mask 74 Is fixed to the holding frame by vacuum suction, and the relative positions of the Z drive unit 75 that drives in the Z direction, and the work alignment mark 76 formed on the substrate 71 and the mask alignment mark 77 formed on the mask 74 are determined. An alignment camera 78 for observation and a light source device 79 are provided.

  The light source device 79 includes a convex lens 80 for uniformly exposing the substrate 71, a mercury lamp 81 as a light source, a known integrator 82 that emits incident light as uniform light as possible, and a shutter 83 that adjusts exposure. And a reflecting mirror 84 that condenses the light emitted from the mercury lamp 81 on the integrator 82.

  The light emitted from the mercury lamp 81 is directly and indirectly irradiated to the integrator 82 via the reflecting mirror 84, and is irradiated from the integrator 82 to the convex lens 80 when the shutter 83 is opened. Since the integrator 82 is disposed at the focal position of the convex lens 80, the light irradiated on the convex lens 80 is refracted to become substantially parallel parallel light, and the substrate 71 is exposed through the mask 74.

  Further, in the exposure apparatus 70, the work alignment mark 76 and the mask alignment mark 77 are observed by the alignment camera 78, and the base 72 is driven in the XYθ direction so that the mask patterns of the substrate 71 and the mask 74 are superimposed. At this time, when another pattern (mask pattern of the mask 74) is formed on the substrate 71 on which the predetermined pattern is formed in the previous process, the positional relationship between the already formed mask pattern and the pattern to be formed in the future It is necessary to perform exposure so as not to cause deviation.

  Therefore, in order to position the original film (mask) and the substrate with high accuracy, it has been proposed to adjust the position so that the mark of the original film and the mark of the substrate enter the imaging area of the CCD camera (alignment camera). (For example, refer to Patent Document 1). In addition, a control device that matches the alignment marks provided on the mask and the printed wiring board has been proposed (see, for example, Patent Document 2).

JP 2000-250232 A (page 4, FIG. 5) JP 2000-250227 A (page 3, FIG. 1)

  However, in the exposure apparatuses disclosed in Patent Document 1 and Patent Document 2 described above, when the substrate becomes large, it tends to expand and contract due to the processing liquid, heat, and the like. If this expansion and contraction is ignored and a new mask pattern is superimposed on the substrate and exposed (overexposure) with a fixed-size mask, there is a problem that a deviation from the mask pattern to be created occurs.

  The present invention has been made in view of the above-described problems, and its purpose is to prevent the occurrence of misalignment of exposure due to expansion or contraction of the substrate to be exposed or the mask when exposing the substrate to be exposed. An object of the present invention is to provide an exposure apparatus and an exposure method that can perform exposure of a mask pattern quickly and with high accuracy.

  In order to achieve the above-described object, an exposure apparatus according to the present invention is characterized by the following (1) to (5).

(1) a substrate to be exposed coated with a photosensitive material;
A mask on which a predetermined mask pattern is formed;
A light source device that projects and exposes the mask pattern onto the substrate to be exposed;
Exposure magnification adjusting means for adjusting an exposure magnification of the mask pattern projected onto the substrate to be exposed;
Control means for controlling the adjustment operation of the exposure magnification adjustment means, wherein the control means uses a predetermined relational expression that associates the adjustment operation amount of the exposure magnification adjustment means with the change amount of the exposure magnification. Controlling the exposure magnification adjusting means in accordance with the amount of expansion / contraction of at least one of the substrate to be exposed and the mask based on the result of the magnification correction calculation.
(2) In the exposure apparatus characterized by the above (1), the light source device exposes the light source, exposure light beam generating means for generating a light beam from light of the light source, and irradiation of the mask from the generated light beam. A light flux adjusting means for adjusting the light substantially parallel to the optical axis,
The exposure magnification adjusting means includes a lens, and a moving means for moving the lens in the optical axis direction,
The control means moves the position of the lens with respect to the light flux adjusting means by the moving means, and changes the irradiation angle of the exposure light irradiated on the mask to control the exposure magnification.
(3) In the exposure apparatus characterized by the above (2), the relational expression is a nonlinear function associating the position of the lens with respect to the light beam adjusting unit and the irradiation angle.
(4) In the exposure apparatus characterized by the above (3), the nonlinear function is optically calculated in an optical system including the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit. It must be a nonlinear function derived from
(5) In the exposure apparatus characterized by the above (3), in the optical system in which the nonlinear function includes the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit, A non-linear function obtained by measuring or preliminarily approximating or complementing discrete values of the irradiation angle at a plurality of positions of the lens with respect to the light beam adjusting means.

  In order to achieve the above-described object, the exposure method according to the present invention is characterized by the following (6) to (10).

(6) Positioning the exposed substrate coated with the photosensitive material and the mask on which the predetermined mask pattern is formed so as to face each other at a predetermined interval;
In an exposure method of projecting and exposing the mask pattern onto the substrate to be exposed by a light source device,
An exposure magnification adjustment step of adjusting an exposure magnification of the mask pattern projected onto the substrate to be exposed by an exposure magnification adjustment means;
A magnification correction calculation using a predetermined relational expression that associates an adjustment operation amount of the exposure magnification adjusting means with a change amount of the exposure magnification corresponding to an expansion / contraction amount of at least one of the substrate to be exposed and the mask. A control step of controlling the exposure magnification adjusting means based on the result;
Be provided.
(7) In the exposure method characterized in (6) above, the light source device exposes the light source, exposure light beam generating means for generating a light beam from the light of the light source, and irradiating the mask from the generated light beam. A light flux adjusting means for adjusting the light substantially parallel to the optical axis,
The exposure magnification adjusting means includes a lens, and a moving means for moving the lens in the optical axis direction,
The control step moves the position of the lens with respect to the light beam adjusting means by the moving means, and changes the irradiation angle of the exposure light applied to the mask to control the exposure magnification.
(8) In the exposure method characterized in (7) above, the control step performs the magnification correction calculation using a nonlinear function that associates the position of the lens with respect to the light beam adjusting unit and the irradiation angle.
(9) In the exposure method characterized in (8) above, the nonlinear function is optically calculated in an optical system including the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit. The nonlinear function derived by
(10) In the exposure method characterized by the above (8), in the optical system including the nonlinear function, the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit, A discrete function of the irradiation angle at a plurality of positions of the lens with respect to the light beam adjusting means is measured in advance to obtain a nonlinear function approximated or supplemented.

According to the exposure apparatus and the exposure method of the present invention, the exposure magnification adjusting means is controlled by the control means so as to correspond to the expansion / contraction amount of at least one of the substrate to be exposed and the mask, and the mask pattern projected onto the substrate to be exposed is controlled. Since the exposure magnification is adjusted, the exposure of the mask pattern can be performed with high accuracy by preventing the occurrence of misalignment of the exposure due to the expansion or contraction of the exposed substrate or the mask when the exposed substrate is exposed. .
Further, the control means controls the exposure magnification adjusting means based on the result of the magnification correction calculation using a predetermined relational expression that associates the adjustment operation amount of the exposure magnification adjusting means with the change amount of the exposure magnification. Thus, the optimum exposure magnification according to the amount of expansion / contraction for each substrate to be exposed and the mask can be set automatically and quickly.

  In addition, since the control means controls the exposure magnification by changing the irradiation angle of the exposure light applied to the mask by the lens of the exposure magnification adjusting means and the moving means of the lens, the exposure magnification can be easily controlled. Can do.

  Since the non-linear function is a non-linear function derived by optical calculation in an optical system including the exposure beam generation unit, the beam adjustment unit, and the lens of the exposure magnification adjustment unit, the position of the lens that realizes a desired irradiation angle Can be easily calculated, whereby the exposure magnification can be adjusted quickly.

  The nonlinear function is obtained by measuring in advance the discrete values of the irradiation angle at a plurality of positions of the lens with respect to the light beam adjusting unit in an optical system including an exposure light beam generating unit, a light beam adjusting unit, and a lens of the exposure magnification adjusting unit. Since it is an approximated or complemented nonlinear function, exposure magnification can be adjusted in consideration of the characteristics unique to the exposure apparatus (more specifically, errors caused by aberrations of optical elements constituting the optical system). The exposure can be performed with high accuracy.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the drawings. 1 is a schematic diagram showing the overall configuration of a first embodiment of an exposure apparatus according to the present invention, FIG. 2 is a block diagram of exposure magnification adjustment of the exposure apparatus shown in FIG. 1, and FIG. 3 is a block diagram of the light source apparatus shown in FIG. FIG. 4 is a schematic diagram showing the overall configuration of a second embodiment of the exposure apparatus according to the present invention.

  As shown in FIG. 1, an exposure apparatus 10 according to the first embodiment of the present invention is a proximity type exposure apparatus, and a substrate to be exposed (hereinafter referred to as a substrate) 11 coated with a photosensitive material, and a predetermined one. A mask 12 on which the mask pattern is formed, a light source device 13 that projects the mask pattern onto the substrate 11 for exposure, a positioning means 14 that positions the substrate 11 and the mask 12 so as to face each other at a predetermined interval, and a substrate An exposure magnification adjusting unit 15 that adjusts the exposure magnification of the mask pattern projected onto the image 11 and a control unit 16 that controls the exposure magnification adjusting unit 15 based on a magnification correction calculation result using a nonlinear function.

  The light source device 13 includes a mercury lamp 17 as a light source, an integrator 18 as an exposure light beam generating means of an optical element that emits incident light with uniform light, and a light beam generated by the integrator 18 is adjusted substantially parallel to the optical axis. A fixed convex lens 19 serving as a light beam adjusting means, a shutter 28 that switches between exposure and non-exposure, and a reflecting mirror 29 that condenses the light emitted from the mercury lamp 17 onto the integrator 18. The fixed convex lens 19 is arranged so that the optical axis of the integrator 18 coincides. An exposure magnification adjusting means 15 is arranged between the integrator 18 and the fixed convex lens 19.

  The exposure magnification adjusting unit 15 includes a movable convex lens 20 and a moving unit 21 that moves the movable convex lens 20 in the optical axis direction. The moving unit 21 includes a drive unit 31 and a ball screw 32. Yes. The ball screw 32 is connected to the drive unit 31 so that its longitudinal direction is parallel to the optical axis. The movable convex lens 20 is held by a lens holding member 30 with the optical axis of the integrator 18 and the fixed convex lens 19 aligned, and the lens holding member 30 is movable in the longitudinal direction of the ball screw 32 (that is, in the optical axis direction). Supported by a ball screw 32. When the drive unit 31 rotates the ball screw 32 forward or backward, the integrator 18 is moved in the optical axis direction together with the lens holding member 30.

  The positioning means 14 has a base 22, an XYθ drive unit 23, and a Z drive unit 24. The base 22 fixes the substrate 11 loaded on the exposure apparatus 10 by vacuum suction. The XYθ drive unit 23 moves or rotates the base 22 in the horizontal direction, that is, in the X direction and the Y direction, and in the rotation direction (θ direction) around the Z axis at the center point according to the input signal of the control means 16. . The Z drive unit 24 vacuum-adsorbs and fixes the mask 12 to the holding frame, and measures a minute interval L1 between the substrate 11 and the mask 12 by a sensor (not shown) so as to keep the minute interval L1 constant. Then, the mask 12 is moved in the Z direction (vertical direction). The minute interval L1 is converted into an electric signal and output to the control means 16.

  A pair of workpiece alignment marks 26 and 26 are formed on the peripheral edge of the substrate 11, and a pair of mask alignment marks 27 and 27 corresponding to the work alignment marks 26 and 26 are formed on the peripheral edge of the mask 12. Has been. A pair of alignment cameras 25 and 25 are arranged vertically above the mask alignment marks 27 and 27. The alignment camera 25 photographs a pair of work alignment marks 26 formed on the substrate 11 and a pair of mask alignment marks 27 formed on the mask 12. Image data obtained by the alignment cameras 25 and 25 is output to the control means 16 as an electrical signal.

  The alignment cameras 25 and 25 are formed when a different pattern (mask pattern of the mask 12) is formed on the substrate 11 on which a predetermined pattern has been formed in the previous process, and a mask pattern to be formed in the future. Used to prevent misalignment of the position. Further, when the substrate 11 or the mask 12 expands or contracts due to heat received during exposure, the relative expansion amount between the substrate 11 and the mask 12 is also accurately measured.

  As shown in FIG. 1 and FIG. 2, the control means 16 has a control circuit unit 33 and a driver 34. The control circuit unit 33 includes a well-known CPU (ie, Central Processing Unit), ROM (ie, Read Only Memory), etc. (all not shown). The control circuit unit 33 detects relative position information between the work alignment marks 26 and 26 and the mask alignment marks 27 and 27 from the image data of the pair of alignment cameras 25 and 25, and the substrate 11 and the mask from the position information. The amount of expansion / contraction relative to 12 is detected, the required exposure magnification is calculated from the amount of expansion / contraction, and the irradiation angle of exposure light that achieves the exposure magnification (that is, the mask 12 is irradiated from the fixed convex lens 19). (Declination angle, which is the maximum angle that the effective exposure light makes with the optical axis). The control circuit unit 33 includes a magnification correction arithmetic circuit using a nonlinear function that associates the position of the movable convex lens 20 with respect to the fixed convex lens 19 and the irradiation angle, and calculates the position of the movable convex lens 20 from the calculated irradiation angle. An electric signal corresponding to the magnification correction calculation result is output to the driver 34. The driver 34 drives the drive unit 31 according to the input electric signal.

The nonlinear function used for the magnification correction calculation of the control circuit unit 33 is a nonlinear function derived by optical calculation in the optical system including the integrator 18, the fixed convex lens 19, and the movable convex lens 20, or the fixed convex lens 19. Is a nonlinear function obtained by approximating or complementing the discrete values of the irradiation angle at a plurality of positions of the movable convex lens 20 in advance. For example, the nonlinear function shown in FIG. 3 is obtained based on the calculation results under the optical conditions shown below and the experimental results under the same optical conditions and measurement conditions.
[Optical conditions]
The incident surface flat of the movable convex lens 20, the exit surface r-430mm, the thickness 14.9mm, the material BK7,
The incident surface r430 mm, the exit surface r-430 mm, the thickness 37 mm, the material BK7 of the fixed convex lens 19,
The distance from the exit surface of the integrator 18 to the entrance surface of the fixed convex lens 19 is 315 mm,
[Calculation]
The declination angle (tan) at the position of r = 100 mm of the fixed convex lens 19 when the position of the movable convex lens 20 relative to the fixed convex lens 19 is moved from 50 mm to 250 mm is calculated.
[Measurement condition]
The position of the movable convex lens 20 relative to the fixed convex lens 19 is changed to 50 mm, 100 mm, 150 mm, 200 mm, and 250 mm, with the gap (small interval L1) between the mask 12 and the substrate 11 being 100 μm.
[Experiment]
Exposure and development are performed, and the exposure magnification at each position of the movable convex lens 20 is measured.

  When the movable lens 20 was at a position of 50 mm, the declination angle was 0.025 as an experimental value and 0.03 as a calculated value. When the movable lens 20 was at a position of 100 mm, the declination angle was an experimental value of 0.015 and a calculated value of 0.0175. When the movable lens 20 is at a position of 150 mm, the experimental value of the declination angle was 0.005, and the calculated value was 0.00. When the movable lens 20 is at a position of 200 mm, the declination angle was an experimental value of -0.025 and a calculated value of 0.02. When the movable lens 20 is at a position of 250 mm, the declination angle has an experimental value of −0.045 and a calculated value of 0.04.

  Next, the operation of the exposure apparatus 10 will be described.

  The mask 12 is fixed to the holding frame of the Z drive unit 24 so that the center position thereof is disposed on the optical axis of the exposure light.

  When performing accurate alignment between the substrate 11 fixed to the base 22 and the mask 12 fixed to the holding frame of the Z drive unit 24, the control means 16 is connected to a line connecting the alignment marks 26 and 26 of the substrate 11. The position of the substrate 11 is adjusted by driving the XYθ drive unit 23 so that the lines connecting the alignment marks 27, 27 of the mask 12 overlap each other and the midpoints of both lines overlap each other (hereinafter referred to as alignment adjustment). . This is based on the image data obtained from the alignment cameras 25 and 25, and the X, Y and θ values to be moved are calculated by the control circuit unit 33 of the control means 16, and the electric signal corresponding to the calculation result is XYθ. This is performed by being given to the drive unit 23. Thereby, the center positions of the substrate 11 and the mask 12 are aligned on the optical axis of the exposure light. In addition, a predetermined minute distance L1 is maintained between the substrate 11 and the mask 12.

  When the substrate 11 or the mask 12 is expanded or contracted, a deviation amount Δ is generated between the workpiece alignment mark 26 and the mask alignment mark 27 after alignment adjustment. That is, the substrate 11 and the mask 12 are originally designed to satisfy Δ = 0, but Δ ≠ 0 due to expansion / contraction between the work alignment marks 26 and 26 or between the mask alignment marks 27 and 27. The value of Δ is obtained from the image data obtained from the alignment cameras 25 and 25 by the control circuit unit 33 of the control means 16 and stored in a memory (not shown) in the control means 16.

  When the substrate 11 or the mask 12 is expanded and contracted, in order to accurately expose the mask pattern formed on the mask 12 to the substrate 11, a deviation amount Δ between the work alignment mark 26 and the mask alignment mark 27, It is necessary to adjust the exposure magnification of the mask pattern based on the minute interval L1. Accordingly, the moving means 21 of the exposure magnification adjusting means 15 moves the position of the movable convex lens 20 relative to the fixed convex lens 19 in the optical axis direction to change the incident angle of the light beam generated by the integrator 18 on the fixed convex lens 19. The exposure magnification is adjusted by changing the irradiation angle of the exposure light applied to the mask 12 from the fixed convex lens 19.

  The required irradiation angle is calculated by the control circuit unit 33 of the control means 16 from the deviation amount Δ and the minute interval L1 stored in the memory of the control means 16. The control circuit unit 33 includes a magnification correction arithmetic circuit that incorporates a nonlinear function that associates the position of the movable convex lens 20 with respect to the fixed convex lens and the irradiation angle, and uses the nonlinear function to calculate from the calculated irradiation angle. The position of the movable convex lens 20 is set.

  Then, based on the set position of the movable convex lens 20, the driver 34 of the control unit 16 outputs a drive current to the drive unit 31 of the moving unit 21 of the exposure magnification adjusting unit 15, and the drive unit 31 rotates the ball screw 32 forward. Alternatively, the movable convex lens 20 is moved in the optical axis direction together with the lens holding member 30 by rotating in the reverse direction, and the movable convex lens 20 is disposed at a predetermined position. Thereby, a desired exposure magnification is set.

  When the shutter 28 of the light source device 13 is opened in this state, the light emitted from the mercury lamp 17 enters the integrator 18 directly and indirectly through the reflecting mirror 29, and the light flux generated by the integrator 18 is generated. The movable convex lens 20 and the fixed convex lens 19 are refracted and transmitted, and the mask 12 is irradiated with a desired irradiation angle. As a result, the mask pattern of the mask 12 is accurately exposed on the substrate 11 at the set desired exposure magnification.

  According to the above-described exposure apparatus 10, the exposure magnification adjustment unit 15 adjusts the exposure magnification of the mask pattern projected onto the substrate 11 based on the exposure magnification magnification correction calculation result using the nonlinear function by the control unit 16. Therefore, even when overexposure is performed on a large substrate, the occurrence of exposure misalignment due to expansion and contraction of the substrate 11 or the mask 12 is prevented, whereby the mask pattern can be exposed with high accuracy. Further, since the exposure magnification is controlled by changing the irradiation angle of the exposure light applied to the mask 12, the exposure magnification can be easily controlled. Furthermore, by performing a magnification correction calculation using a predetermined nonlinear function that associates the position of the movable convex lens 20 with respect to the fixed convex lens 19 and the irradiation angle, an optimum exposure magnification corresponding to the amount of expansion / contraction for each of the substrate 11 and the mask 12 is obtained. Can be set automatically and quickly.

  Next, a second embodiment of the exposure apparatus according to the present invention will be described with reference to FIG. In the second embodiment, the same members and the like as those of the exposure apparatus 10 of the first embodiment described above are denoted by the same reference numerals in the drawing, and the description thereof is omitted.

  As shown in FIG. 4, the exposure apparatus 40 according to the second embodiment of the present invention includes a substrate 11, a mask 12, a positioning unit 14, an exposure magnification adjustment unit 15, a control unit 16, and a light source device 41. , And alignment cameras 25 and 25.

  The light source device 41 includes a mercury lamp 17, a reflecting mirror 29 that condenses the light emitted from the mercury lamp 17, and a plane mirror 42 for reversing the optical path that inverts the light reflected by the reflecting mirror 29 and collects it on the integrator 18. , An integrator 18 and a concave mirror 43 that inverts the light beam generated by the integrator 18 and irradiates the mask 12 substantially perpendicularly. An exposure magnification adjusting means 15 is disposed between the integrator 18 and the concave mirror 43.

  In the exposure apparatus 40, when the substrate 11 or the mask 12 is expanded or contracted, the control means 16 calculates the required exposure magnification, and the exposure light irradiation angle that achieves the exposure magnification (that is, from the concave mirror 43). The declination angle, which is the maximum angle formed by the exposure light applied to the mask 12 with the optical axis, is calculated. Based on the calculated irradiation angle, the position of the movable convex lens 20 with respect to the concave mirror 43 is set by magnification correction calculation using a nonlinear function, and the movable convex lens 20 is arranged at a predetermined position by controlling the moving means 21.

  Then, the light emitted from the mercury lamp 17 is directly and indirectly applied to the plane mirror 42 via the reflecting mirror 29, and the light inverted by the plane mirror 42 is condensed on the integrator 18, and the movable convex lens 20 is moved. The concave mirror 43 is reached. Then, the exposure light reflected by the concave mirror 43 is irradiated onto the mask 12 at a desired irradiation angle, and the mask pattern of the mask 12 is accurately exposed onto the substrate 11 at a desired exposure magnification.

  According to the exposure apparatus 40 described above, the exposure magnification adjustment unit 15 adjusts the exposure magnification of the mask pattern projected onto the substrate 11 based on the exposure magnification magnification correction calculation result using the nonlinear function by the control unit 16. Therefore, even when overexposure is performed on a large substrate, the occurrence of exposure misalignment due to expansion and contraction of the substrate 11 or the mask 12 is prevented, whereby the mask pattern can be exposed with high accuracy. Moreover, since the exposure magnification is controlled by changing the irradiation angle of the exposure light applied to the mask 12, the exposure magnification can be easily controlled. Furthermore, by performing a magnification correction calculation using a predetermined nonlinear function that correlates the position of the movable convex lens 20 with respect to the concave mirror 43 and the irradiation angle, an optimum exposure magnification according to the amount of expansion / contraction for each of the substrate 11 and the mask 12 is obtained. It can be set automatically and quickly.

  The exposure apparatus of the present invention is not limited to the above-described embodiments, and appropriate modifications and improvements can be made.

  For example, as the moving means 21 for driving the movable convex lens 20 of the exposure magnification adjusting means 15, a fluid such as air or liquid is used instead of the combination of the lens holding member 30, the ball screw 32, and the driving unit 31 shown in the figure. A driving means or a combination mechanism of a gear and a link can be applied.

  In the above embodiment, the movable magnification lens 20 is provided in the exposure magnification adjusting means 15 and the movable convex lens 20 is moved with respect to the fixed convex lens 19. However, the integrator 18 is replaced with the fixed convex lens 19 by omitting the movable convex lens 20. You may move it.

1 is a schematic diagram showing the overall configuration of a first embodiment of an exposure apparatus according to the present invention. It is a block diagram of exposure magnification adjustment of the exposure apparatus shown in FIG. It is a table | surface which shows the nonlinear function of the magnification correction calculation in the optical system of the light source device shown in FIG. It is the schematic which shows the whole structure of 2nd Embodiment of the exposure apparatus which concerns on this invention. It is the schematic which shows the whole structure of the conventional exposure apparatus.

Explanation of symbols

10, 40 Exposure apparatus 11 Substrate (substrate to be exposed)
DESCRIPTION OF SYMBOLS 12 Mask 13,41 Light source device 14 Positioning means 15 Exposure magnification adjustment means 16 Control means 17 Mercury lamp (light source)
18 Integrator (exposure beam generation means)
19 Fixed lens (light flux adjusting means)
20 Movable lens (lens)
21 Moving means 43 Concave mirror (light flux adjusting means)

Claims (10)

An exposed substrate coated with a photosensitive material;
A mask on which a predetermined mask pattern is formed;
A light source device that generates irradiation light for projecting and exposing the mask pattern onto the substrate to be exposed;
Exposure magnification adjusting means for adjusting an exposure magnification of the mask pattern projected onto the substrate to be exposed;
Control means for controlling the adjustment operation of the exposure magnification adjustment means, wherein the control means uses a predetermined relational expression that associates the adjustment operation amount of the exposure magnification adjustment means with the change amount of the exposure magnification. An exposure apparatus that controls the exposure magnification adjusting means in accordance with an expansion / contraction amount of at least one of the substrate to be exposed and the mask based on a result of magnification correction calculation. The light source device adjusts the generated light beam substantially parallel to the optical axis and generates exposure light for irradiating the mask with the light source, an exposure light beam generating means for generating a light beam from the light of the light source, Means,
The exposure magnification adjusting means includes a lens, and a moving means for moving the lens in the optical axis direction,
The said control means moves the position of the said lens with respect to the said light beam adjustment means by the said movement means, changes the irradiation angle of the said exposure light irradiated to the said mask, and controls the said exposure magnification. 2. The exposure apparatus according to 1.   The exposure apparatus according to claim 2, wherein the relational expression is a nonlinear function that associates the position of the lens with respect to the light beam adjusting unit and the irradiation angle.   The non-linear function is a non-linear function derived by optical calculation in an optical system including the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit. 4. The exposure apparatus according to 3.   In the optical system in which the nonlinear function includes the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit, the irradiation angle is discrete at a plurality of positions of the lens with respect to the light beam adjustment unit. 4. The exposure apparatus according to claim 3, wherein the exposure apparatus is a non-linear function obtained by approximating or complementing the measured value in advance. Positioning the exposed substrate coated with the photosensitive material and the mask on which the predetermined mask pattern is formed to face each other at a predetermined interval,
In an exposure method of projecting and exposing the mask pattern onto the substrate to be exposed by a light source device,
An exposure magnification adjustment step of adjusting an exposure magnification of the mask pattern projected onto the substrate to be exposed by an exposure magnification adjustment means;
A magnification correction calculation using a predetermined relational expression that associates an adjustment operation amount of the exposure magnification adjusting means with a change amount of the exposure magnification corresponding to an expansion / contraction amount of at least one of the substrate to be exposed and the mask. A control step of controlling the exposure magnification adjusting means based on the result;
An exposure method comprising: The light source device includes a light source, an exposure light beam generation unit that generates a light beam from light of the light source, and a light beam adjustment unit that adjusts exposure light applied to the mask from the generated light beam substantially parallel to an optical axis; Including
The exposure magnification adjusting means includes a lens, and a moving means for moving the lens in the optical axis direction,
7. The control step of controlling the exposure magnification by moving a position of a lens with respect to the light beam adjusting means by the moving means and changing an irradiation angle of the exposure light applied to the mask. An exposure method according to 1.   The exposure method according to claim 7, wherein the control step performs the magnification correction calculation using a nonlinear function that associates the position of the lens with respect to the light beam adjusting unit and the irradiation angle.   The non-linear function is a non-linear function derived by optical calculation in an optical system including the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit. 9. The exposure method according to 8.   In an optical system including the non-linear function, the exposure light beam generation unit, the light beam adjustment unit, and the lens of the exposure magnification adjustment unit, the irradiation angle is discrete at a plurality of positions of the lens with respect to the light beam adjustment unit. 9. The exposure method according to claim 8, wherein a value is measured in advance to obtain an approximate or complemented nonlinear function.

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