CN107450276B

CN107450276B - Exposure device

Info

Publication number: CN107450276B
Application number: CN201710395242.9A
Authority: CN
Inventors: 桥本典夫
Original assignee: Orc Manufacturing Co Ltd
Current assignee: Orc Manufacturing Co Ltd
Priority date: 2016-06-01
Filing date: 2017-05-27
Publication date: 2021-06-11
Anticipated expiration: 2037-05-27
Also published as: CN107450276A; JP6723831B2; JP2017215535A

Abstract

The invention provides an exposure device, which measures the feeding amount of a long substrate with high precision and draws patterns on two surfaces of the substrate under the state of ensuring the flatness of the substrate. The exposure device comprises: a 1 st exposure unit including an array of light modulation elements; a 1 st substrate holding unit for holding a part of the long substrate in the longitudinal direction in a planar shape; a 1 st relative movement unit that relatively moves the 1 st exposure unit and the 1 st substrate holding unit in a longitudinal direction of the long substrate; a folding unit that folds back a transport path of the long substrate; a 2 nd exposure unit including an array of light modulation elements; a 2 nd substrate holding unit for holding a part of the long substrate in the longitudinal direction in a planar shape; and a 2 nd relative movement unit that relatively moves the 2 nd exposure unit and the 2 nd substrate holding unit in the longitudinal direction of the long substrate.

Description

Exposure device

Technical Field

The present invention relates to an exposure apparatus that draws a pattern on both surfaces of a long substrate fed from a supply reel and wound around a winding reel during conveyance of the long substrate.

Background

In general, as a base material of an electronic circuit board (printed circuit board) used in a mobile phone, a mobile device, or the like, for example, a material obtained by processing a long substrate (photosensitive long film) having a thickness of 0.1mm or less and a length of 500mm or more (e.g., 100m) into a roll shape is used. In recent years, a direct exposure apparatus (maskless exposure apparatus) has been desired which directly irradiates a substrate with a drawing light without using a transfer mask to draw a pattern on such a long substrate.

As a direct exposure apparatus for patterning a long substrate, for example, an exposure apparatus as described in patent document 1 is known, but in such an exposure apparatus, a pattern can be exposed only on one surface of a long substrate, and it is necessary to take up the substrate after exposure, set the roll again on the input side, and perform an exposure step again, which is low in production efficiency. On the other hand, in order to form electronic circuits on both surfaces of a long substrate using a direct exposure apparatus, an exposure apparatus has been studied in which a pattern is formed by irradiating drawing light on both surfaces of a substrate as described in patent document 2.

Patent document 1: japanese patent laid-open No. 2006-102991

Patent document 2: japanese patent laid-open publication No. 2005-121959

The exposure apparatus of patent document 2 has a problem that it is not possible to provide an exposure stage having a size covering an exposure range in a structure in which drawing light is irradiated to both surfaces of a substrate. The exposure stage has the effect of measuring the feed amount of the substrate with high accuracy and improving the planarity of the substrate, and it is difficult to draw a high-accuracy pattern on the substrate without the exposure stage.

Disclosure of Invention

The present invention has been made in view of the above problems, and an object of the present invention is to provide a direct exposure apparatus that measures the feed amount of a long substrate with high accuracy and draws a pattern on both surfaces of the substrate while ensuring the planarity of the substrate.

The exposure device comprises: a 1 st exposure section having a light modulation element array and irradiating the 1 st surface of the long substrate with pattern light modulated by the light modulation element array; a 1 st exposure stage for holding a part of the long substrate in a longitudinal direction in a planar shape; a 1 st relative movement unit which relatively moves the 1 st exposure part and the 1 st exposure stage in the longitudinal direction of the long substrate; a folding unit that folds back a transport path of the long substrate; a 2 nd exposure section having a light modulation element array for irradiating the 2 nd surface of the long substrate with pattern light modulated by the light modulation element array; a 2 nd exposure stage for holding a part of the long substrate in a longitudinal direction in a planar shape; and a 2 nd relative movement unit which relatively moves the 2 nd exposure part and the 2 nd exposure stage in the longitudinal direction of the long substrate. By using such an exposure apparatus, both surfaces of the long substrate can be exposed by using the exposure stage. Further, since the 1 st exposure portion and the 2 nd exposure portion are irradiated with pattern light downward, the patterns can be exposed on both surfaces of the long substrate under the same conditions.

Further, the 1 st and 2 nd relative movement units move the 1 st and 2 nd exposure tables, respectively, in synchronization in opposite directions along the longitudinal direction of the long substrate, and the 1 st and 2 nd exposure portions modulate pattern light irradiated to the long substrate, respectively, in accordance with the movement of the 1 st and 2 nd exposure tables. The exposure apparatus includes a substrate supply unit that feeds out a long substrate, and the substrate supply unit adjusts a speed at which the long substrate is fed out in synchronization with the movement of the 1 st exposure stage, and similarly, the exposure apparatus includes a substrate winding unit that winds up the long substrate, and the substrate winding unit adjusts a speed at which the long substrate is wound up in synchronization with the movement of the 2 nd exposure stage. Thus, since the long substrate can be conveyed without providing the buffer portion for the substrate, it is possible to reduce an unnecessary region where the pattern cannot be exposed on both surfaces of the long substrate, such as the vicinity of the roll end portion.

In addition, since the substrate supply unit and the substrate winding unit are disposed on the same side of the exposure apparatus, efficiency of setup change operations such as reel change is improved.

Further, since the 1 st relative movement unit and the 2 nd relative movement unit are provided at the same height, the height of the apparatus can be suppressed, and a compact exposure apparatus can be realized.

According to the exposure apparatus of the present invention, the amount of feed of the substrate can be measured with high accuracy for a long substrate, and patterns can be drawn on both surfaces of the substrate while ensuring the planarity of the substrate.

Drawings

Fig. 1 is a front view showing the overall structure of an exposure apparatus of the present invention.

Fig. 2 is a plan view showing the overall structure of the exposure apparatus of the present invention.

Fig. 3 is a front view showing the structure of an exposure head of the direct exposure apparatus of the present invention.

Description of the reference symbols

1: an exposure device; 10: a reel driving section; 11: a supply reel; 12: winding the reel; 20: the 1 st exposure processing part; 22: aligning the camera; 23: a 1 st exposure unit; 24: an exposure stage; 30: a fold-back section; 40: a 2 nd exposure processing unit; 42: aligning the camera; 43: a 2 nd exposure unit; 44: an exposure stage; BF: a stand; w: a long substrate.

Detailed Description

Fig. 1 is a front view showing the overall configuration of an exposure apparatus 1 as a roll-to-roll direct exposure apparatus of the present invention. Fig. 2 is a plan view showing the overall structure of the exposure apparatus 1. In fig. 2, a part of the long substrate (workpiece) W is drawn so as to be seen through (wavy line portion) and so as to be hidden by the long substrate W.

The exposure apparatus 1 includes, in order along a conveyance path of a long substrate W: a reel driving unit 10 for supplying and winding a long substrate W; a 1 st exposure processing unit 20 for forming an electronic circuit by exposing a pattern on a 1 st surface of the long substrate W; a folding section 30 that folds back the conveyance path; and a 2 nd exposure processing unit 40 for forming an electronic circuit by exposing a pattern on the 2 nd surface of the long substrate W. Here, the 1 st surface of the long substrate W refers to the upper surface side of the substrate unwound from the supply reel 11 of the reel driving unit 10, and the 2 nd surface refers to the lower surface side of the substrate unwound from the supply reel 11.

The long substrate W is a sheet-like substrate made of a copper-clad laminate or the like coated with a photosensitive material such as a photoresist, and has a length of several tens to several hundreds meters. After exposure, the base material of the FPC board is formed through steps such as development, etching, and cutting.

The reel drive unit 10 includes a supply reel (substrate supply unit) 11, a winding reel (substrate winding unit) 12, and a guide roller 13, and rotationally drives the supply reel 11 and the winding reel 12 by a drive system (not shown). In addition, the reel driving unit 10 may include a sensor for detecting the position of the end surface of the long substrate W, a mechanism for adjusting the tension applied to the long substrate W, and the like.

Between the reel drive unit 10 and the 1 st exposure processing unit 20 are provided: a guide roller 14 for changing the conveying direction of the long substrate W by 90 °; a substrate brake roller 16 that brakes (holds) the substrate; an edge sensor 21 that detects a substrate end surface; and a correction roller 15 for changing the conveying direction of the long substrate W by 90 ° and adjusting the position of the end face of the substrate in accordance with the output of the edge sensor 21.

The 1 st exposure processing section 20 has an exposure stage 24 (1 st exposure stage), a pair of alignment cameras 22 (see fig. 2), and a 1 st exposure unit (exposure section) 23, and exposes a pattern on the 1 st surface of the long substrate. Here, the moving direction (conveying direction) of the long substrate W in the exposure processing unit 20 is defined as an X direction, a direction (thickness direction) perpendicular to the long substrate W is defined as a Z direction, and a direction perpendicular to the X direction and the Z direction is defined as a Y direction.

The 1 st exposure unit 23 includes a plurality of exposure heads (not shown) regularly arranged at positions vertically spaced upward from the long substrate W by a predetermined distance.

Fig. 3 is a schematic view showing the structure of 1 exposure head. Light emitted from a light source (mercury lamp or the like) OP1 is made parallel via an illumination optical system OP2 and a return mirror OP3 and enters an optical modulator array OP 4. The light modulation element array OP4 is, for example, a DMD (Digital Micro-mirror Device) in which a plurality of micromirrors are two-dimensionally arranged. The light (UV) modulated by the light modulation element array OP4 is imaged on the long substrate by the imaging optical system OP 5. Further, the exposure head has a focusing optical system OP6 that adjusts the imaging position in the optical axis direction.

For example, japanese patent application laid-open No. 2003-084444 discloses a technique for multiple exposure of a pattern using a DMD, which is a known technique widely used in practical use. Further, for example, japanese patent application laid-open No. 2003-195512 discloses a technique of drawing 1 pattern using a plurality of heads, and this technique is a known technique that has been widely put into practical use.

The exposure stage 24 holds the back surface of the long substrate W in a planar state by suction (for example, vacuum suction), and is movable in the X direction and the Z direction. That is, the stage moving unit (1 st relative movement means) 25 movably supported by a guide rail along the X direction is provided on the mount BF, and the raising and lowering unit 26 for raising and lowering the exposure stage 24 is supported. The stage moving unit 25 is provided with a means (not shown) for measuring the position of the stage moving unit 25, such as a linear scale or a laser displacement meter, and the amount of movement of the exposure stage 24 (i.e., the amount of feed of the long substrate W) can be accurately measured.

The exposure stage 24 is moved up and down by the lift unit 26 between an upper end position in contact with the back surface of the long substrate W and a lower end position spaced apart from the back surface of the long substrate W. The stage moving unit 25 is movable in the X direction in forward and reverse directions (downstream direction and upstream direction). The stage moving section 25 constitutes a relative movement unit that relatively moves the exposure stage 24 and the exposure unit 23 in the longitudinal direction of the long substrate W. The range (area) in which the exposure stage 24 can suction and hold the long substrate W at a time is, for example, 620(X) × 520(Y) mm.

The pair of alignment cameras 22 are provided upstream of the exposure unit 23, and take images of alignment marks (not shown) provided on the long substrate W. The image captured by each alignment camera 22 is subjected to image processing by an image processing unit (not shown) and used to calculate a correction amount for aligning the long substrate W with the exposure unit 23.

The folding portion (folding unit) 30 is provided with

guide rollers

31 and 33, and a substrate brake roller 32 that brakes the substrate. Since the

guide rollers

31 and 33 bend the long substrate W by 90 ° at a time, the conveyance direction of the long substrate W is reversed by 180 ° before and after the turn-back section 30. Accordingly, the 1 st surface of the long substrate W is the lower surface side and the 2 nd surface is the upper surface side after the folding portion 30.

Between the folding-back unit 30 and the exposure processing unit 40, the long substrate W is conveyed through a passage provided inside the gantry (base unit) BF. Further, between the folding back section 30 and the exposure processing section 40, there are provided: a guide roller 16; a guide roller 17 for braking the substrate by changing the conveying direction of the long substrate W by 90 °; an edge sensor 41 for detecting the substrate end surface; and a correction roller 15 for changing the conveying direction of the long substrate W by 90 ° and adjusting the position of the end face of the substrate in accordance with the output of the edge sensor 21.

The 2 nd exposure processing section 40 has an exposure stage 44 (the 2 nd exposure stage), a pair of alignment cameras 42 (see fig. 2), and a 2 nd exposure unit (exposure section) 43, and exposes a pattern on the 2 nd surface of the long substrate.

The alignment camera 42, the 2 nd exposure unit 43, the exposure stage 44, the stage moving unit 45, and the elevating unit 46 have the same functions as the alignment camera 22, the 1 st exposure unit 23, the exposure stage 24, the stage moving unit 25, and the elevating unit 26 of the 1 st exposure processing unit 20, respectively. On the other hand, the 1 st exposure processing section 20 and the 2 nd exposure processing section 40 are different in the conveyance direction of the long substrate.

That is, the 1 st exposure processing unit 20 and the 2 nd exposure processing unit 40 are symmetrically arranged in the opposite direction to the X direction, and operate in the opposite direction to the X direction. For example, referring to fig. 1, when the exposure stage 24 of the 1 st exposure processing unit 20 moves leftward to perform scanning exposure on the 1 st surface of the long substrate W, the exposure stage 44 of the 2 nd exposure processing unit 40 moves rightward to perform scanning exposure on the 2 nd surface of the long substrate W.

In the exposure apparatus of the present invention, the exposure operation is performed while the conveyance speeds of the long substrates W in the respective portions are made to coincide with each other. For example, the supply reel 11 unwinds the substrate in synchronization with the movement of the exposure stage 24. The above-mentioned actions are realized as follows: the reel rotation speed is always adjusted according to the remaining amount of the long substrate W supplied to the reel 11. The same is true for the relationship between the movement of the exposure stage 44 and the winding of the winding reel 12. The exposure stage 24 and the exposure stage 44 also operate in synchronization.

In this way, by synchronously conveying the long substrate W at the respective portions with the conveyance speeds being the same, it is possible to shorten the region (the discard region for setup change) where the pattern cannot be exposed on both surfaces of the substrate, which is generated in the vicinity of the roll end portion of the long substrate W.

In the exposure apparatus of the present invention, the stage moving unit 25 and the stage moving unit 45 are provided on the same height base provided on the same stage BF. By adopting such a configuration, the structure of the exposure apparatus becomes simple, and the exposure apparatus becomes compact.

Further, in the exposure apparatus of the present invention, the supply reel 11 and the take-up reel 12 are disposed on the same side of the exposure apparatus (in fig. 1, the right end portion of the exposure apparatus) by the configuration in which the folding-back section 30 is provided. With this arrangement, the replacement of the reel becomes easy, and the productivity is improved.

Next, the operation of the exposure apparatus of the present invention will be described. The operation of the exposure apparatus 1 is to alternately perform a conveyance step of conveying the long substrate W and a preparation step of stopping conveyance of the long substrate W and preparing for the next conveyance step.

In the transport step, the reel drive unit controls the rotation speed of the supply reel 11 and the winding reel 12 to carry out the feeding and winding of the long substrate W at a predetermined speed. The exposure stages 24 and 44 are moved in the X direction while the long substrate W is being attracted, and the 1 st exposure unit 23 and the 2 nd exposure unit 43 expose the pattern on the 1 st surface and the 2 nd surface of the long substrate using the drawing data corrected based on the alignment result in the preparation step. In addition, in the conveying step, the

substrate brake rollers

16 and 32 are released from braking.

In the preparation step, the reel driving section stops the supply reel 11 and the take-up reel 12, and the

substrate brake rollers

16 and 32 are brought into a braking state. The substrate suction of the exposure tables 24 and 44 is released, and the lift unit is lowered to separate the exposure tables from the long substrate W. Next, the exposure tables 24 and 44 are returned to the scanning start position, and the elevating unit is raised. The

substrate brake rollers

16 and 32 are released from braking, and the exposure tables 24 and 44 perform suction of the long substrate W. The exposure stage and the reel drive unit are driven, and the

alignment cameras

22 and 42 are caused to perform imaging of the alignment marks and position correction processing of the drawing data. Thereafter, the positions of the exposure tables 24 and 44 are adjusted so that the long substrate W reaches the pattern exposure start position.

By repeating the above 2 steps, patterns can be formed on both surfaces of the long substrate W.

In the above embodiment, the description has been made using fig. 1, but the present invention can be applied even when the substrate conveyance direction is different from that of fig. 1. For example, the 1 st exposure processing unit 20 and the 2 nd exposure processing unit 40 may be switched to reverse the conveyance direction of the long substrate W. In this case, the roles of the supply spool 11 and the take-up spool 12 may be interchanged. Alternatively, the mirror image relationship structure of fig. 1 may be adopted such that the reel driving section 10 is at the left end portion of the exposure apparatus.

In the above embodiment, the 1 st exposure processing unit and the 2 nd exposure processing unit are at the same height, but in order to shorten the length of the exposure apparatus in the X direction, the exposure processing units may be arranged so as to partially overlap in the Z direction.

Further, as necessary, substrate cushion members such as dancer rollers may be provided at each portion of the conveyance path of the long substrate. In this case, the area in the vicinity of the roll end of the long substrate where double-side exposure is not possible is increased, but the conditions can be relaxed with respect to synchronization of the respective portions, and the transport error factor can be reduced.

As described above, according to the exposure apparatus of the present invention, by using the exposure stage for a long substrate, it is possible to obtain an exposure apparatus that can measure the feed amount of the substrate with high accuracy and draw a pattern on both surfaces of the substrate while ensuring the planarity of the substrate.

Claims

1. An exposure apparatus, comprising:

a 1 st exposure section having a light modulation element array and irradiating the 1 st surface of the long substrate with pattern light modulated by the light modulation element array;

a 1 st exposure stage for holding a part of the long substrate in a longitudinal direction in a planar shape;

a 1 st relative movement unit that relatively moves the 1 st exposure section and the 1 st exposure stage in a longitudinal direction of the long substrate;

a folding unit that folds back a transport path of the long substrate;

a 2 nd exposure unit having a light modulation element array for irradiating the 2 nd surface of the long substrate with pattern light modulated by the light modulation element array;

a 2 nd exposure stage for holding a part of the long substrate in a longitudinal direction in a planar shape; and

a 2 nd relative movement unit that relatively moves the 2 nd exposure section and the 2 nd exposure stage in a longitudinal direction of the long substrate,

the 1 st relative movement unit and the 2 nd relative movement unit move the 1 st exposure stage and the 2 nd exposure stage in opposite directions along the longitudinal direction of the long substrate in synchronization with each other, and the 1 st exposure portion and the 2 nd exposure portion modulate pattern light incident on the long substrate in accordance with the movement of the 1 st exposure stage and the 2 nd exposure stage, respectively.

2. The exposure apparatus according to claim 1,

the 1 st exposure part and the 2 nd exposure part respectively irradiate the pattern light downwards.

3. The exposure apparatus according to claim 1 or 2,

the exposure apparatus includes a substrate supply unit for feeding out the long substrate,

the substrate supply unit adjusts a speed of feeding out the long substrate in synchronization with the movement of the 1 st exposure stage.

4. The exposure apparatus according to claim 3,

the exposure apparatus includes a substrate winding unit for winding the long substrate,

the substrate winding unit adjusts a speed of winding the long substrate in synchronization with the movement of the 2 nd exposure stage.

5. The exposure apparatus according to claim 4,

the substrate supply unit and the substrate winding unit are arranged on the same side of the exposure device.

6. The exposure apparatus according to claim 1 or 2,

the 1 st relative movement unit and the 2 nd relative movement unit are arranged on a base part with the same height.