JPH04147147A - Film exposure device and its method - Google Patents

Abstract

PURPOSE:To carry out an exposure in an optimum state by detecting the positional relation of the projected image of the mark of a reticle side and a hole or a light transmitting part, with respect to a frame, and moving a reticle and a projecting lens. CONSTITUTION:A frame of a film exposed by a film feeding mechanism 60 is carried up to an exposure position on a device by step feeding. At this time, light having wavelength not to sensitize the film F is projected from an irradiation part 1 through the mark of the reticle side. When the mark of a film side reaches the projecting position of the mark of the reticle side, the light having the wavelength for alignment and passing the mark of the film side to be the hole is received by a detecting part 40. It is detected that a frame of the film F is carried up to the exposure position, thereon, and a signal is sent from a system controller 50 to the film feeding mechanism 60, to stop the carrying. Thus, the exposure can be carried out in the optimum state.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

The present invention relates to a film exposure apparatus suitable for manufacturing film circuit boards, and in particular, it is capable of position control and magnification control for each frame of transported film. [0002]

[Conventional technology]

Photolithography technology is known as a technology for applying microfabrication to the surface of an object. In addition to semiconductor integrated circuits, this technology has recently been applied to the production of film circuit boards used to mount electronic components. [0003] Such an exposure apparatus includes an irradiation section having a light source, a reticle on which a circuit pattern to be exposed is formed by being irradiated with light emitted from the irradiation section, and an image set on the reticle is projected. It consists of a lens and a stage that sets the film at the projection position to form the exposure position. In the conventional apparatus, when performing projection exposure, it is necessary to adjust the magnification of the projected image before starting projection exposure. This magnification adjustment work can be done, for example, in Japanese Patent Application Laid-Open No. 1-19149.
This is carried out by the method described in Publication No. 3. That is, this is performed by moving the projection lens position adjustment mechanism and the reticle position adjustment mechanism in the optical axis direction while monitoring images of patterns, alignment marks, etc. projected onto the exposure surface using a monitor system. [0004] However, when the projection lens position adjustment mechanism or reticle position adjustment mechanism is operated to displace the projection lens or reticle in the optical axis direction in order to perform force plate focusing, the focus of the projected image is thereby displaced. Sometimes it happens. [0005] In order to solve these problems, Japanese Patent Application No. 2-813
A projection lens based on a focus set as shown in No. 37,
A method of adjusting the magnification while maintaining the positional relationship between the reticle and the projection plane of the film has been proposed. [0006]

[Problem to be solved by the invention]

However, in conventional apparatuses, the magnification is accurately set only before actually starting exposure. That is, when the rotation light operation is started, its projection image is projected at the reticle position and the projection lens position set before the start. If the positions of the reticle and projection lens become out of order for some reason, they will naturally deviate from these set values. As a result, exposure is performed with the magnification shifted, and if the apparatus continues to operate without noticing this situation, a large amount of film will be wasted. [0007] On the other hand, even if the position of the reticle and the position of the projection lens are accurate, a similar problem will occur if the transported film is not set at the correct position. On the other hand, by periodically performing the adjustment work that was done before the start of the exposure work,
Although the above problems can be solved to some extent, it is extremely troublesome for humans to perform such tasks on a regular basis. [0008] An object of the present invention is to provide a film exposure apparatus and a film exposure method that can perform exposure in an optimal state even after starting an exposure operation. [0009] [Means for Solving the Problems 1] In order to achieve the above object, the film exposure apparatus of the present invention is a film exposure apparatus that sequentially exposes a circuit pattern along the length direction of a strip-shaped film. an irradiation section and a position where light from the irradiation section is irradiated;
A reticle having a reticle-side mark separate from a circuit pattern to be projected, a projection lens for projecting an image of the reticle, a reticle position adjustment mechanism for adjusting the position by displacing the reticle in the optical axis direction and horizontal direction, and a projection lens. a projection lens position adjustment mechanism that adjusts the position by displacing the image in the optical axis direction, and a film having holes or transparent parts corresponding to the reticle side marks at the projection position of the image by the projection lens.
A film feeding mechanism that feeds the film in steps one frame at a time, a detection means that detects the positional relationship between the projected image of the mark on the reticle side and the hole or the transparent part for each frame of the film after the step feeding, and This system consists of a system controller that moves the reticle and projection lens based on signals, and the method is to move the reticle in the horizontal direction after stepping one frame of the film using the film advance mechanism. The positional relationship between the side mark and the hole or transparent part on the film side is detected, and based on this detected value, the reticle position adjustment mechanism moves the reticle horizontally to align the reticle side mark with the hole or transparent part. In addition, based on the detected value, the reticle is moved in the horizontal direction by a reticle position adjustment mechanism to control the positional relationship between the marks on the reticle side and the holes or transparent parts on the film side. ,
The reticle position adjustment mechanism allows you to move the reticle in the optical axis direction.
This is to control magnification adjustment by moving the projection lens in the optical axis direction using a projection lens position adjustment mechanism. [0010]

[Effect]

According to the present invention, the reticle is moved in the horizontal direction for each frame of the transported film, and the positional relationship between the mark on the reticle and the hole or transparent portion on the film is detected. By this detection, the reticle and the projection lens can be displaced in the optical axis direction to control the magnification, and the reticle can be displaced in the horizontal direction (direction perpendicular to the optical axis) to control the position. [0011]

Example 1 The present invention will be described in detail below. This apparatus sequentially exposes a circuit pattern on a reticle 10 along the length of a strip-shaped film F. [0012] FIGS. 1, 2, and 3 are explanatory diagrams of a film exposure apparatus according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an irradiation section that includes a light source 11, a mirror that reflects the emitted light from the light source 11, and an integrator lens. As the light source 11, one that efficiently emits light to which the resist is sensitive, such as an ultra-high pressure mercury lamp, is used. [0013] Reference numeral 10 denotes a reticle, which is placed at a position where light from the irradiation section 1 is irradiated. The reticle 10 includes a circuit pattern to be projected and transferred onto the film F, as well as reticle-side marks. This reticle-side mark is configured, for example, by providing a cross-shaped transparent part in a rectangular opaque part. The film-side mark is composed of, for example, a round hole for each frame on the film F. [0014] Reference numeral 12 denotes a reticle position adjustment mechanism, which is composed of, for example, a servo motor. A projection lens 20 projects an image of the irradiated reticle 10. This projection lens 2
0 has a resolution of, for example, an exposure line width of 10 μm. 21 is a projection lens position adjustment mechanism of this projection lens 20. The system controller 50 drives the reticle position adjustment mechanism 12 and the projection lens position adjustment mechanism 21. 30 is a stage, as shown in FIG. 2, it has suction holes 3 for vacuum suctioning the film F only during exposure.
1 is provided. 40 is a detection section, which is composed of an objective lens 41, a condensing lens 42, and a light receiver 43 made of a photodiode and the like. Reference numeral 60 denotes a film feeding mechanism, which steps one frame of the film F to the position where the image is projected by the projection lens 20. 61 is a feed roller, 63 is a press roller, 64 is a sprocket roller, 65 is a press roller, 66.67 is an auxiliary roller, 68 is a supply roller,
69 is a take-up roller. [0015] Next, the operation of the device will be explained. First, the film transport mechanism 60 transports one frame of film to be exposed in steps to the exposure position in the apparatus. At this time, the image is projected onto the film F from the irradiation unit 1 through the reticle-side mark using a wavelength (alignment wavelength) that does not expose the film F while being transported. Then, as the film F is transported, when the film-side mark reaches the projection position of the reticle-side mark, the light of the alignment wavelength that has passed through the film-side mark, which is a hole, is transmitted to the detection unit 4.
The light is received at 0. This means that it is detected that one frame of film F has been transported to the exposure position, and the system controller 50 sends a signal to the film transport mechanism 60 to stop transport. In this state, one frame of the film is roughly conveyed, but more precise positioning is performed. This operation will be explained using FIGS. 3, 4, and 5. FIG. 3 shows a reticle 10, and in addition to the circuit pattern 12 projected onto the film, the above-mentioned reticle-side mark 13 is formed. FIG. 4 shows a film in which, in addition to the exposure position FIO of the circuit pattern 12, there is also a hole F13 as a mark on the film side.
are formed with the circuit pattern 12 in between. [0017] The reticle 10 is scanned (moved) in the X direction along the feeding direction of the film F. The electrical signal generated in the detection unit 40 at this time is as shown in FIG. When the projected image of the mark 13 on the reticle side begins to overlap the hole 13 on the film side, the projected position of the rising part molecule 1, the flat part 2 whose overlapping area is approximately constant, and the projection position of the mark 13 on the reticle side deviates from the hole 13. It becomes a pulse-like waveform consisting of a falling portion molecule 3 at the beginning. [0018] Therefore, in the X direction, the position at time T3 corresponding to, for example, the center of the flat portion molecule 2 with the largest overlapping area of marks is detected and stored in the system controller 50 as information on the position of the reticle 10. . [0019] Then, the reticle 10 continues to move in the X direction and detects another hole 13 in the same manner. After the position detection of the two holes 13 in the X direction is completed in this manner, the reticle 10 is similarly moved in the Y direction to detect the positions of the two holes 13. That is, the position of the step-fed film can be detected by detecting the position of these two film-side holes or transparent parts. This detected value, that is, the system controller 5
The reticle 10 can be moved on a horizontal plane in the rotational directions of the X direction and the Y direction according to the position information sent to the reticle 0, so as to correspond to one frame of the transported film F. FIG. 4 shows the situation. However, if the reticle 10 or the projection lens 20 is misaligned in the optical axis direction, the magnification changes and cannot be adjusted by the above-mentioned control alone. This state is shown in FIG. [0020] In order to correct the projection magnification accuracy from the state shown in FIG. , respectively, to correct the magnification of the projected image. This magnification correction may be performed in parallel with the above-described alignment control for horizontally moving the reticle 10, or may be performed before or after. [0021] After the correction of the projection magnification and the projection position is completed, the light of the exposure wavelength is applied to one of the films set at the exposure position of the film.
Expose the circuit pattern onto each frame. In this way, the magnification and position of the projected image can be detected and corrected for each frame of film stepwise feeding. [0022] In the above embodiment, the image projected onto the film-side mark 10 is transmitted to a CC, instead of the light receiver 40, or together with it, for example.
Focusing can also be performed using an image sensor such as D. [0023]

【Effect of the invention】

As explained above, according to the film exposure apparatus of the present invention, the image projected for each frame of the film to be exposed is detected, and when the magnification is misaligned, the reticle and projection lens are exposed to light. It is possible to adjust each frame of the film by moving the reticle in the axial direction and, if the position is misaligned, by moving the reticle horizontally to follow the misalignment.

[Brief explanation of drawings]

[Figure 1] FIG. 1 is an explanatory diagram showing one embodiment of the present invention.

[Figure 2] FIG. 2 is a side sectional view showing the configuration of the main part of FIG. 1. FIG.

[Figure 3] FIG. 2 is a plan view showing details of the reticle of FIG. 1;

FIG. 4 is an explanatory diagram illustrating the projection magnification accuracy on the film in this example.

FIG. 5 is an explanatory diagram illustrating the projection magnification accuracy on the film in this example.

FIG. 6 is a waveform diagram illustrating the states of FIGS. 4 and 5 using electrical signals.

[Explanation of symbols]

1 Irradiation section 10 Reticle 12 Reticle position adjustment mechanism 20 Projection lens 21 Projection lens position adjustment mechanism 40 Detection part 50 System controller F Film

【Document name】

drawing

[Figure 1] Sat-111--------+
A

[Figure 2]

[Figure 3]

[Figure 4]

[Figure 5]

[Figure 6] Mu

Claims (2)

[Claims] 1. A film exposure device that sequentially exposes a circuit pattern along the length of a strip-shaped film, comprising an irradiation section and a position where light from the irradiation section is irradiated. A reticle that has a reticle-side mark separate from the circuit pattern to be printed, a projection lens that projects an image of the reticle, a reticle position adjustment mechanism that adjusts the position by displacing the reticle in the optical axis direction and horizontal direction, and a projection lens. A projection lens position adjustment mechanism that adjusts the position by displacing it in the optical axis direction, and a film that step-feeds the film frame by frame, which has holes or transparent parts corresponding to the reticle side marks, at the projection position of the image by the projection lens. a feeding mechanism; a detection means for detecting the positional relationship between the projected image of the mark on the reticle side and the hole or the transparent portion for one frame of the film after step feeding; A film exposure device comprising: a system controller for moving a lens; and a system controller for moving a lens. 2. A film exposure method using the film exposure apparatus according to claim 1, wherein the reticle is moved in the horizontal direction after one frame of the film is stepped back by the film transport mechanism, and the reticle is moved horizontally. The positional relationship between the side mark and the hole or transparent part on the film side is detected, and based on this detected value, the reticle position adjustment mechanism moves the reticle horizontally to align the reticle side mark with the hole or transparent part. In addition, based on the detected value, the reticle is moved in the horizontal direction by a reticle position adjustment mechanism to control the positional relationship between the marks on the reticle side and the holes or transparent parts on the film side. ,
The reticle position adjustment mechanism allows you to move the reticle in the optical axis direction.
A film exposure method characterized in that magnification adjustment is controlled by moving a projection lens in the optical axis direction using a projection lens position adjustment mechanism.