JP2886675B2 - Film exposure apparatus and film exposure method - Google Patents

Description

The present invention relates to a film exposure apparatus and a film exposure method suitable for producing a film circuit board used for mounting, for example, a TAB (Tape Automated Bonding) type electronic component. About.

[Conventional technology]

As a technique for performing fine processing on the surface of an object, a photolithography technique is known. This technology has been applied not only to semiconductor integrated circuits but also recently to the production of film circuit boards used for mounting TAB-type electronic components.

However, if the transferred circuit pattern is misaligned, mounting errors will occur in the case of a circuit board, so it is necessary to align the circuit pattern so that the image of the photomask pattern is exposed at the correct position on the film being transported. It is said. The accuracy of the alignment is required to be, for example, within ± 10 μm.

Conventionally, this alignment has been performed as follows. That is, first, before the exposure processing, the exposure sample provided with the alignment mark is arranged on the stage,
The light from the lamp is exposed through a photomask provided with an alignment mark to project an image of the alignment mark on the photomask side, and is formed through the semi-transparent thin film to form an image of the alignment mark on the exposed sample. Both images of the mask-side alignment mark are observed with a microscope.

Operate the photomask position adjustment mechanism to move the photomask in a direction perpendicular to the optical axis so that the image of the alignment mark on the photomask and the alignment mark on the exposure sample match, and perform alignment. Do.

In order to correctly position one frame of the film at the position of the image plane of the projection lens when the photomask aligned in this manner is set as an object (surface), the distance of film feed by the feed roller is set in advance. A sprocket roller is arranged before the position of the image plane to improve the accuracy in the feed direction. Further, the stage having the positioning pins is raised for one frame of the film stopped after the film is fed by a predetermined distance, and the positioning pins are fitted into the perforations of the one frame portion of the film from below, and the image is formed. Positioning is performed in a plane perpendicular to the optical axis with respect to the plane. Positioning with respect to the image plane in the optical axis direction is performed by a holding plate that suppresses one frame of the film pushed up from below by the stage.

As described above, in the conventional alignment, before starting the operation of the exposure apparatus, the photomask is arranged at a correct position by an exposure sample, and the feed distance of the step feed of the feed roller, the accuracy of the feed direction, and the stage By simply fitting the positioning pins into the perforations and the holding plate, only one frame of the film to be exposed is arranged at a position considered to be correct with respect to the photomask. That is, no feedback control is performed on the film during the exposure.

[Problems to be solved by the invention]

However, there is a limit in accuracy in mechanical alignment using such sprocket rollers, positioning pins, and the like. For example, alignment of about ± 10 μm or less cannot be performed by this method anymore.

This is because, for example, a film long in a belt shape may meander slightly but not perfectly in a straight line. In this case, even if the film is forcibly transported straight by the sprocket roller, the film may be transported on the stage with a deviation beyond an allowable limit.

In addition, the positioning pins provided on the stage are forcibly fitted and positioned in the perforations of the film. However, if the film is conveyed with a deviation exceeding the allowable limit as described above, the perforations are damaged and spread, and the positioning pins are spread. , The accuracy of positioning is further reduced.

Also, the thickness of the film used for the substrate tends to be thin for reasons such as cost reduction.For example, when the thickness is 30 μm or less, the method using the positioning pin is no longer used.
The problem of perforation damage is large and cannot be adopted.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a film exposure apparatus and a film exposure method which enable projection of an image at a correct position while eliminating the need to insert a positioning pin into perforation, and which have a higher precision of a pattern exposure and transfer position. It is in.

[Means for solving the problem]

In order to achieve the above object, a film exposure apparatus of the present invention is a film exposure apparatus that sequentially exposes a circuit pattern to a plurality of frames arranged along the length direction of a belt-shaped film, and an irradiation unit, A photomask arranged at a position where light from the irradiation unit is irradiated, a position adjustment mechanism of the photomask, a projection lens that projects an image of the irradiated photomask, and a film at a position where the image is projected by the projection lens. And a film feed mechanism for step-feeding one frame at a time. At least two or more film-side alignment marks are formed on the strip-shaped film corresponding to each frame, and the photomask is formed on the film. Along with the circuit pattern to be projected and transferred, a photomask-side alignment mark is formed corresponding to each of the film-side alignment marks. Characterized in that it is.

In the film exposure apparatus of the present invention, it is preferable that the alignment mark on the film side is constituted by a hole or a light transmitting portion formed in the film.

In addition, an optical system for re-projecting the primary projection image of the alignment mark on the photomask side projected on the projection position of the image by the projection lens, and a detector for receiving a secondary projection image by the optical system are provided. Is preferred.

Further, a second optical system for dividing and projecting a primary projection image of the photomask-side alignment mark to a position different from the position where the detector is provided, and a secondary projection image by the second optical system. It is preferable to include an image sensor for receiving the image and a monitor mechanism connected via the image sensor.

The film exposure method of the present invention is a film exposure method using the above-described film exposure apparatus, and when one frame of the film is step-feeded by the film feed mechanism, the film-side alignment mark pertaining to the one frame is The detection unit detects whether the projection position of the image of the alignment mark on the photomask side is reached, stops one frame by a signal from the detection unit, and then performs exposure.

Another film exposure method of the present invention is a film exposure method using the above-described film exposure apparatus, in which one frame of the film is step-feeded by a film feed mechanism, and the film side related to one frame stopped after this step-feed is performed. The position of the photomask is controlled by driving the photomask position adjustment mechanism so that the image of the photomask-side alignment mark is projected on the position of the alignment mark,
Thereafter, exposure is performed.

In the film exposure method of the present invention, one frame of the film is step-feeded by the film feed mechanism, and after this step feed, the photomask position adjustment mechanism is driven to include the film-side alignment mark for the stopped one frame. In the area, the primary projection image of the photomask-side alignment mark is scanned, and the light transmitted through the film-side alignment mark is received by the detector, and the rising and falling curves of the output signal from the detector are detected. The positions of the output levels that are equal to each other are stored, and based on the stored positions, the photomask position adjustment mechanism is driven so that the image of the photomask-side alignment mark matches the film-side alignment mark. Control the position of the mask and then It is preferable to perform the exposure.

[Action]

If the position of the projected image of the alignment mark on the photomask is aligned with the alignment mark on the film,
The position of one frame of the film matches the photomask.

If one frame of the film is stopped after detecting that the position of the projected image of the alignment mark on the photomask side matches the alignment mark on the film side, the accuracy of the stop position is improved.

By adjusting the position of the photomask so that the alignment mark on the photomask matches the position of the alignment mark on the film that stopped after the step feed, even if the paper is conveyed out of position, it can be followed. As a result, the position of the photomask is changed, so that the position accuracy of the projected image is increased.

If the film exposure apparatus includes an optical system for re-projecting the primary projection image of the photomask-side alignment mark and a detector for receiving a secondary projection image by the optical system,
Since the light transmitted through the alignment mark on the film side is reliably received by the detector, the detector generates an appropriate output signal, thereby enabling appropriate position control.

Further, using this film exposure apparatus, the positions of the same output level in the rising curve and the falling curve of the output signal from the detector are respectively stored, and the position control of the photomask is performed based on the stored positions. If this is done, the photomask can be stopped at a position where the overlapping area between the image of the photomask-side alignment mark and the film-side alignment mark is substantially constant, so that more reliable position control is possible.

When monitoring the projected image of the alignment mark on the photomask side by using an exposure apparatus having an image sensor and a monitor mechanism, it is necessary to visually check whether or not the correct position control is performed. Can be.

〔Example〕

FIG. 1 is an explanatory view of a film exposure apparatus according to one embodiment of the present invention. In this apparatus, the circuit pattern of the photomask M is sequentially exposed along the length direction of the belt-shaped film F.

Reference numeral 10 denotes an irradiation unit, which incorporates a lamp 11 such as an ultra-high pressure mercury lamp or the like, which efficiently emits light having sensitivity of the resist.

The irradiating unit 10 has a built-in filter for switching between light having an exposure wavelength at which the resist has sensitivity (solid line in FIG. 4) and light having an alignment wavelength at which the resist has no sensitivity. During alignment, the photomask M is irradiated with light having an alignment wavelength, and during exposure is irradiated with light having an exposure wavelength. As this filter, for example, a sharp cut filter that cuts light having a sensitivity of 500 nm or less is used,
At the time of exposure, the sharp cut filter is retracted from the optical path.

M is a photomask, which is arranged at a position where light from the irradiation unit 10 is irradiated. In this photomask M,
As shown in FIG. 2, a film-side alignment mark (hereinafter, referred to as a “film-side mark”) FM, which will be described later, together with a circuit pattern MP to be projected and transferred onto the film F.
A photomask-side alignment mark (hereinafter referred to as “photomask-side mark”) MM is formed corresponding to each of the above. The photomask side mark MM is configured by providing a cross-shaped transparent portion on a rectangular opaque portion. MA is a coarse adjustment mark.

As shown in FIG.
Two film side marks FM are formed corresponding to each of F10. In this example, the film side mark FM is constituted by a round hole.

MM 'is an image of the photomask-side mark, and the image MM' of the photomask-side mark is a region including the film-side mark FM by the movement operation of the photomask M, which will be described later, that is, the projection position of the image by the projection lens. Film F
Virtual surface FK of film side mark FM consisting of upper surface and hole
Scanned over.

In the present embodiment, the film-side mark FM and the photomask-side mark MM are provided two in the width direction of the film F. However, the present invention is not limited to this, and two marks may be provided in the length direction or the oblique direction of the film. Good. Further, three or four or more may be provided.

M10 is a photomask position adjusting mechanism, which includes a photomask holder M11 and a servomotor M12. When the servo motor M12 is driven by a signal from a system controller 50 described later, the photomask holder M11 moves and the photomask M is controlled to follow. This photomask holder M11 can adjust the position of the photomask M in two directions (X direction and Y direction) perpendicular to each other in a plane perpendicular to the optical axis. Adjustment for rotating the mask M (adjustment of θ) is possible. Therefore, actually, three servo motors M12 for driving the photomask holder M11 are provided so as to be able to drive each of X, Y, and θ.

Reference numeral 20 denotes a projection lens which projects an image of the irradiated photomask M. The projection lens 20 has a resolution of, for example, an exposure line width of about 5 μm.

Reference numeral 30 denotes a stage. As shown in FIG. 4, the upper surface is a reference surface, and is provided with a vacuum suction hole 31 for blowing out air when the film F is fed stepwise and for vacuum suctioning the film during exposure. 32 is a vacuum pump and 34 is a valve. In this example, the vacuum suction hole 31 also serves as a reverse air hole for floating the film F with air when the film F is step-fed, 33 is a compressor, and 35 is a valve.
Numerals 36 and 37 cause the front and rear portions of the film F to float during the step feeding of the film F. Valves 34, 35
Is controlled by a signal from a system controller 50 described later.

Reference numeral 40 denotes a detection unit. As shown in FIG. 4, the detection unit 40 is a unit type having an objective lens 41, a condenser lens 42, and a detector 43. In this example, the detection unit 40 is embedded in the stage 30, and the objective lens 41 is arranged at a position facing the hole as the film-side mark FM. The detector 43 is a converter made of a high-sensitivity photoelectric conversion element, for example, a phototube or a photodiode.
Further, an image sensor can be used as the detector 43. 44 is an amplifier.

 50 is a system controller including a CPU.

Reference numeral 60 denotes a film feed mechanism for step-feeding one frame F10 of the film F to a position where an image is projected by the projection lens 20. The feed roller 61 is driven by a motor 62. The drive of the motor 62 is started by a signal from the system controller 50, and is decelerated by a signal from the system controller 50, as described later, and then stopped by a signal from the system controller 50 that has received a signal from the detection unit 40. 63 is a press roller, 64 is a sprocket roller,
65 is a press roller, 66 and 67 are auxiliary rollers, 68 is a take-out reel, and 69 is a take-up reel.

Note that the rough adjustment mark MA is one in which the photomask M is arranged in advance within a position controllable range when position control of the photomask M described later is performed.

Next, an embodiment of the film exposure method of the present invention using the film exposure apparatus of FIG. 1 will be described.

When one frame F10 of the film F is step-advanced by the film feed mechanism 60, a detection unit determines whether or not the film-side mark FM related to this one-frame F10 has reached the position of the image of the photomask-side mark MM. Detect by 40.

First, the driving start signal from the system controller 50 to the motor 62 is transmitted, when the motor 62 is time to send a rotation to the film F at a constant speed v ₁ of FIG. 5 becomes t ₁ of FIG. 5,
The speed of the motor 62 is decelerated to v ₂ in FIG. 5 by a signal from the system controller 50. The t ₁ of time is previously set according to the length or the like of one frame F10 of the film.

While being decelerated in the v _2, it receives a stop signal from the system controller 50 which processes the signal from detector 40, the motor 62 stops rotating. This time is t _{2 in} FIG.
It is.

The generation of the stop signal by the system controller 50 is performed as follows. As shown in FIG. 3, one frame F10 of the film is sent, and the film side mark FM provided corresponding to one frame F10 is replaced with the photomask side mark MM.
When the image projection position is reached, the film side mark
Alignment wavelength light transmitted by FM (dotted line in Fig. 4)
As a result, the detection unit 40 generates a signal. FIG. 6 shows the change over time in the intensity of this signal.

As shown in FIG. 4, two detectors 40 are provided in the width direction of the film F, and two signals in the form shown in FIG. 6 are sent to the system controller 50. Since the feed direction of the film F is not normally a perfect right angle in the width direction, the signals from the two detectors 40 are sent with a slight time lag.

Therefore, in this embodiment, the detection unit 40 that is input with a delay
At the falling edge of the signal from the (first 6 Figure T ₃₎ so as to generate a stop signal, to perform the signal processing in the system controller 50, thereby stopping the motor 62 completely (Sixth
T ₂₎ of the figure.

Note that the time at which the motor 62 is completely stopped by the stop signal from the system controller 50 is not limited to the falling time (T _{3 in} FIG. 6) of the signal from the detection unit 40 input late. By setting the correction value in advance, any of a slow rising, a fast falling, and a fast rising may be used.

If the speed is reduced in this way and then stopped by a signal from the detection unit 40, the accuracy of the stop position becomes very high.

When one frame F10 of the film is stopped by a stop signal from the system controller 50, the system controller 5
From 0, a signal is sent to the valves 34 and 35 to close the compressor 33 and open the vacuum pump 32. This allows
One frame F10 is vacuum-adsorbed to the stage 30.

In this state, the position of the photomask M is controlled to perform exposure with higher projection position accuracy. That is, the photomask position adjusting mechanism M10 is driven so that the image of the corresponding photomask mark MM is projected onto each position of the film mark FM of one frame F10, and the position of the photomask M is shifted in the X direction. In addition, the position of the photomask M is adjusted by performing tracking control while moving in the Y direction and rotating about the optical axis.

More specifically, when the position of the photomask M is scanned in the X direction along the feed direction, the electric signal generated in the detection unit 40 is, as shown in FIG. a rising portion T ₁ start overlapping the side mark FM, a flat portion T ₂ of both of the overlapping area is substantially constant, the falling portion T ₃ Metropolitan projection position of the photomask-side mark MM begins to deviate from the film-side mark FM It becomes a pulse-like waveform.

Therefore, the position to stop the photomask M final in the X direction, it is preferable overlapping area of the mark is set to the position at time t ₃ when corresponds to, for example, the center of the flat portion T ₂ is the maximum. Therefore, the system controller 50
The information of the position of the photomask M at the time of scanning and the value of the signal from the detection unit 40 at that time are stored. These are processed to determine the optimum position of the photomask M in the X direction, and the servo motor M12 is used. To the drive signal.

In the same manner as described above, the photomask M
To generate a signal in the detection unit 40, determine the optimum position of the photomask M in the Y direction by signal processing of the system controller 50, and send a drive signal to the servo motor M12 in the Y direction.

The position adjustment in the X direction and the Y direction is performed using one of the detection units 40. After the position adjustment in the X direction and the Y direction is completed, scanning is performed by rotating the photomask M about the optical axis while receiving a signal from the other detection unit 40. At this time, the signal from the other detection unit 40 has the same shape as that shown in FIG. 6, and therefore, the rotation direction (θ) is determined by the information on the rotation angle of the photomask M and the value of the signal from the detection unit 40 at that time.
The optimal position of the photomask M in the (direction) is determined, and a drive signal is sent to the servo motor M12 in the θ direction. Thus, the position adjustment of X, Y, and θ of the photomask M is performed.

After the alignment of the photomask M is completed as described above, the sharp cut filter described above is retracted so that the light of the exposure wavelength is emitted from the irradiation unit 10, and the frame F10 held at the projection position is set. Then, the circuit pattern MP of the photomask M is exposed.

Next, another embodiment of the film exposure method of the present invention using the film exposure apparatus of FIG. 1 will be described.

This embodiment is substantially the same as the method of the above-described embodiment, but in this example, when the signal from the detection unit 40, which is input with a delay, rises (T _{1 in} FIG. 6). The system controller 50 performs signal processing so as to generate a stop signal.

Then, the position control of the photomask M after the step feed is performed as follows.

By driving the photomask position adjusting mechanism M10, the area including the film mark FM is scanned with the primary projection image of the photomask mark MM, and the light transmitted through the film mark FM is received by the detector 43, position of the mutually equal output levels in rising curve and the falling curve of the output signal from the detector 43, the position t ₄ and t ₅ when e.g. 1/10 outputs of the output value in the T ₂ of the FIG. 9 is detected each stored, based on the stored respective positions, for example, to drive the photomask position adjusting mechanism M10 to stop the midpoint t ₆ between t ₄ and t _5.

According to such a method, the photomask M can be stopped at a position where the overlapping area between the image of the photomask-side mark MM and the film-side mark FM is substantially constant, so that more reliable position control is possible. Become.

Next, another embodiment of the film exposure apparatus of the present invention will be described.

As shown in FIG. 7, the film exposure apparatus includes, for example, a half mirror 46 that divides and projects the primary projection image of the photomask-side mark MM to a position different from the position where the detector 43 is provided. A second optical system, an image sensor 71 for receiving a secondary projection image by the second optical system, and a monitor mechanism 72 connected via the image sensor 71.

By using such a film exposure apparatus, the image of the projected photomask-side mark MM can be monitored by the image sensor 71, and the operator can visually check whether or not the correct position control is performed. You can check.

Although the embodiments of the present invention have been described above, various changes can be made in the film exposure apparatus of the present invention as described below.

The film-side mark FM is not limited to a hole, and may be a mark in which a translucent film or the like is attached to the hole. According to such a configuration, no problem occurs due to dust entering the detection unit 40.

As shown in FIG. 8, a light-blocking shutter 15 is interposed in an exposure light path to shield light, and light from a lamp 11 is transmitted from a lamp 11 through a light-receiving hole 17 provided in an elliptical condenser mirror 16 by, for example, an optical fiber 18 to the photomask side. According to the method of aligning by irradiating the mark MM and retracting the light-blocking shutter 15 from the exposure optical path at the time of exposure, the light of the exposure wavelength is used as it is as the light for alignment without using a sharp cut filter. be able to.

Also, in the film exposure method of the present invention, various changes can be made as described below.

In the above-described embodiment, the position of the photomask M is controlled after one frame F10 of the film is stopped by a signal from the detection unit 40. However, the present invention is not limited to this. After stopping the motor 62 so as to send the distance without depending on the signal from the detection unit, the photomask M
May be performed. Also, only the operation of stopping one frame F10 of the film by the signal from the detection unit 40,
If the projected position of the image of the mark MM on the photomask side is the optimum position, the position control of the photomask M for each frame is unnecessary. For example, after stopping the film a plurality of times about 10 times, The position control of the mask M may be performed once.

When the position control of the photomask M is performed, if the film side mark FM is a perfect circle or the like having a known radius, the rising state of the detection signal can be predicted. Is stored in the system controller 50 in advance, the position can be controlled only by detecting the rising time of the detection signal. If the size of the film-side mark FM is extremely smaller than the size of the photomask-side mark MM, the detection signal has a peak shape as shown in FIG. The position control may be performed according to the position corresponding to the peak without consideration.

〔The invention's effect〕

According to the film exposure apparatus of the present invention, at least two or more photomask-side marks are formed on a photomask, and a film-side mark corresponding to each of the photomask-side marks is formed on one frame of the film. Therefore, by making the two marks coincide with each other, highly accurate exposure can be performed.

In particular, if the optical system includes an optical system that re-projects the primary projection image of the alignment mark on the photomask side and a detector that receives a secondary image captured by the optical system, more appropriate position control is performed. be able to.

According to the film exposure method of the present invention, one frame of the film is stopped after detecting that the photomask-side mark and the film-side mark coincide with each other, so that a high degree of exposure can be performed.

According to another film exposure method of the present invention, even when the sheet is conveyed with a misalignment, the position of the photomask is changed accordingly, so that the position accuracy of the projected image is increased, and the accuracy is further improved. High exposure can be performed.

In particular, by storing the positions of the same output level in the rising curve and the falling curve of the output signal from the detector, and controlling the position of the photomask based on the stored positions, a more reliable position can be obtained. Control becomes possible.

In addition, when using a film exposure apparatus including an image sensor and a monitor mechanism to monitor the projected image of the alignment mark on the photomask side, it is visually determined whether or not the correct position control is performed. You can check.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a film exposure apparatus according to an embodiment of the present invention,
FIG. 2 is an explanatory view of a photomask-side alignment mark, FIG. 3 is an explanatory view of a film-side alignment mark, and FIG. 4 is a view of a main part of the apparatus shown in FIG. FIG. 5 is a speed curve diagram of the motor,
6, 9 and 10 are waveform diagrams of the detection signal, FIG.
FIG. 8 is an explanatory view showing an example of a detecting section, and FIG. 8 is an explanatory view showing an example of irradiating light from an irradiating section to a photomask-side alignment mark. F: Film, M: Photomask 10: Irradiation section, 11: Lamp 15: Light-blocking shutter, 16: Elliptical condensing mirror 17: Lighting hole, 18: Optical fiber MP: Circuit pattern FM: … Film side alignment mark MM …… Photomask side alignment mark M10 …… Photomask position adjustment mechanism M11 …… Photomask holder M12 …… Servo motor, 20 …… Projection lens 30 …… Stage, 31 …… Vacuum Suction hole 32 Vacuum pump 33 Compressor 34, 35 Valve 36, 37 Lifting roller 40 Detector 41 Objective lens 42 Condenser lens 43 Detector 44 … Amplifier, 46… Half mirror 50… System controller 60… Film feed mechanism 61… Feed roller 62… Motor 63, 65… Holding roller 64… Sprocket roller 66, 67… Auxiliary roller , 68 …… Unwind reel 6 9 ... take-up reel, 71 ... image sensor 72 ... monitor mechanism

Claims (7)

(57) [Claims] 1. A film exposure apparatus for sequentially exposing a circuit pattern to a plurality of frames arranged along the length direction of a strip-shaped film, comprising: an irradiation unit; and a position to which light from the irradiation unit is irradiated. A photomask disposed in the photomask, a position adjustment mechanism for the photomask, a projection lens for projecting the illuminated image of the photomask, and a film feed mechanism for stepwise feeding the film to the image projection position by the projection lens At least two or more film-side alignment marks are formed on the strip-shaped film corresponding to each frame, and the photomask is formed with a circuit pattern to be projected and transferred onto the film, A film, wherein a photomask-side alignment mark is formed corresponding to each of the film-side alignment marks. Exposure equipment. 2. A film exposing method using the film exposing apparatus according to claim 1, wherein when one frame of the film is step-advanced by the film feed mechanism, a film-side alignment mark pertaining to the one frame. Detecting whether the image has reached the projection position of the image of the alignment mark on the photomask side, stopping one frame by a signal from the detection unit, and then performing exposure. Method. 3. A film exposing method using the film exposing apparatus according to claim 1, wherein one frame of the film is step-advanced by a film feeding mechanism, and the film side alignment related to one frame stopped after the step-advancing. Film exposure, wherein a photomask position adjustment mechanism is driven to control the position of the photomask so that an image of the alignment mark on the photomask side is projected onto the position of the mark for use, and then exposure is performed. Method. 4. The film exposure apparatus according to claim 1, wherein the alignment mark on the film side is formed by a hole or a light transmitting portion formed in the film. 5. The film exposure apparatus according to claim 4, wherein an optical system for re-projecting a primary projection image of the photomask-side alignment mark projected on the projection position of the image by the projection lens, and And a detector for receiving a next projected image. 6. A film exposing method using the film exposing apparatus according to claim 5, wherein one frame of the film is step-advanced by a film feeding mechanism, and after this step-advancing, the photomask position adjusting mechanism is driven. This allows the primary projection image of the photomask-side alignment mark to be scanned in a region including the stopped film-side alignment mark for one frame, and causes the detector to receive light transmitted through the film-side alignment mark. And storing the positions of the output levels that are equal to each other in the rising curve and the falling curve of the output signal from the detector. Based on the stored positions, the image of the photomask-side alignment mark is used for film-side alignment. Photomask position adjustment mechanism to match the mark A film exposure method, comprising: controlling the position of a photomask by driving the photomask; and then performing exposure. 7. The film exposure apparatus according to claim 5, wherein the primary projection image of the alignment mark for photomask is
A second optical system that divides and projects the image at a position different from the position where the detector is provided, an image sensor that receives a secondary projection image by the second optical system, and is connected via the image sensor. A film exposure apparatus comprising a monitor mechanism.