JPH06277866A - Laser beam machining device - Google Patents

Abstract

PURPOSE:To inexpensively provide a driving system with high accuracy in a laser beam machining device possible to work a large area by driving a mask and a substrate. CONSTITUTION:This device is constituted of a mask 1 equipped with a light transmitting part transmitting a laser beam 22 from a light source and a non- transmission part, a holding stage 41 loading a substrate 3 on the mask l and on the same plane iuxtaposed with this mask 1, and an image-formation optical system 5 forming an image so that the image surface of sight passing through the mask 1 is formed on the plane of the substrate 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a via hole (VIA HO) in a printed circuit board by laser light using a mask, for example.
It relates to a laser processing device for processing (LE).

[0002]

2. Description of the Related Art FIG. 13 is a diagram showing a configuration of an optical processing device proposed by the present inventors in recent years. In the figure, the laser beam 22 from the light source is applied to only a part of the mask 1. At this time, the image forming lens 51 forms an image of the light 21 passing through the mask 1 on the substrate 3 and processes the substrate 3 with the laser light 2.
The mask 1 and the substrate 3 are continuously driven in the x and y directions or are synchronously driven by a step-and-scan driving method to irradiate the laser beam 22 on the entire surface of the mask 1 to process the entire area of the substrate 3.

[0003]

However, the optical processing apparatus having the above-described structure is processed in the case where the mask 1 is provided with a minute hole pattern having a diameter of, for example, several tens of μm. The accuracy of the hole diameter depends on the amount of distortion of the processing lens 51 used, the mask 1 and the substrate 3
It also depends on the accuracy of synchronous drive with. Therefore, a highly accurate XY processing stage is required for driving the mask 1 and the substrate 3, and a processing stage needs to be prepared for both the driving of the mask 1 and the driving of the substrate 3. Therefore, there is a problem that the processing accuracy is low and the cost of the apparatus itself is extremely high.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object thereof is to reduce the cost of the drive system in a laser processing apparatus that drives a mask and a substrate to process a large area. Moreover, it is to provide a laser processing apparatus that can perform with high accuracy.

[0005]

In order to achieve such an object, the present invention drives a mask and a substrate in a mechanically connected state on the same plane or on two planes at an arbitrary speed ratio. It was done like this.

[0006]

In the laser processing apparatus according to the present invention, since the mask and the workpiece are driven in a mechanically connected state, the problem of synchronization deviation does not occur, and the drive system can be controlled with high precision. Since no device is required, an inexpensive and highly accurate processing device can be realized.

[0007]

Embodiments of the present invention will be described in detail below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional view showing the construction of an embodiment of a laser processing apparatus according to the present invention. In the figure, 1 is a mask that transmits light only in the portion corresponding to the pattern to be processed, 21 is laser light that passes through the mask 1 and contributes to processing, 22 is laser light from a light source, and 2 is an imaging lens 51. The laser light is imaged on the substrate 3.
Further, 3 is a substrate as a workpiece, 41 is a holding stage on which the mask 1 and the substrate 3 are placed, and 5 is an image forming optical system for forming an image of the light passing through the mask 1 on the substrate 3 and transferring it. Yes, in this case, the transfer magnification of this imaging optical system 5 is 1. Further, the image forming optical system 5 having the transfer magnification of 1 is shown in FIG.
As shown in (1), the magnification is -1, that is, the lens 51 for forming an inverted image and the reflecting mirrors 52, 53, 54, 55. In FIG. 1, 7 is a laser beam 22.
Is a mirror that reflects.

Next, the operation will be described. In such a configuration, in the laser light 22 applied to the mask 1, only the laser light 21 corresponding to the portion to be processed passes through the mask 1 and is transferred onto the substrate 3 by the imaging optical system 5 for processing. Be seen. At this time, the imaging optical system 5 forms an erect image with a magnification of 1 on the substrate 3. Since the area on the mask 1 irradiated with light is limited, the holding stage 41 is driven to scan the light on the entire surface of the mask 1 and at the same time to drive the substrate 3 in synchronization therewith.

In the configuration of this embodiment, the mask 1 and the substrate 3 are
And are driven at the same speed at the same time. Since the magnification of the imaging optical system 5 is 1, even if the driving speeds of the mask 1 and the substrate 3 are the same, the pattern on the mask 1 is accurately imaged on the substrate 3. By placing the mask 1 and the substrate 3 on one holding stage 41 and driving them in this way, a synchronization deviation of the synchronous drive does not occur in principle, so that extremely highly accurate processing can be performed.

(Embodiment 2) FIG. 3 is a sectional view showing the structure of a laser processing apparatus according to another embodiment of the present invention. In the figure, the mask 1 and the substrate 3 are installed so as to be driven on respective predetermined planes (plane A, plane B), and one end side thereof can rotate about a fulcrum 421 in a direction indicated by an arrow. To the connecting rod 42 and the sliding surface 422.
It is configured to be driven by being coupled by. In this case, the imaging lens 51 used in the imaging optical system 5 is an erecting image lens with a magnification M> 0. The drive speed ratio at this time is given as M = b / a using the values of the distance a from the fulcrum 421 to the plane A and the distance b from the fulcrum 421 to the plane B in FIG. Therefore, if the values of the distance a and the distance b are changed according to the magnification M of the imaging lens 51, it is possible to drive at an arbitrary speed ratio, and in principle no drive synchronization deviation occurs. Further, the driving force may be given to only one of the mask 1 and the substrate 3.

(Third Embodiment) FIG. 4 is a sectional view showing the structure of a laser processing apparatus according to still another embodiment of the present invention. In the figure, the mask 1 and the substrate 3 are installed so as to be driven on predetermined planes (plane A, plane B), respectively, and pivot in the direction indicated by the arrow with a fulcrum 421 at the center thereof. It is configured to be driven by being coupled to the possible connecting rod 42A by a sliding surface 422.

In such a structure, since the mask 1 and the substrate 3 are driven in opposite directions, the imaging lens 5
Example 1 is the same as Example 1 except that an inverted image lens with a magnification M <0 is used.
Is the same as.

(Embodiment 4) FIG. 5 is a diagram showing the construction of another embodiment of the laser processing apparatus according to the present invention. FIG. 5 (a) is a sectional view and FIG. 5 (b) is a plan view. . In FIG. 5, the mask 1 and the substrate 3 are arranged on the mask mounting table 11 and the substrate mounting table 39, respectively, and one rotating shaft 4 is provided.
3 is installed on a rotary stage 41A supported by a rotary shaft 43 of the drive mechanism 43A. In addition, at a predetermined position on the rotary stage 41A, the substrate mount 39
Drive mechanism 61 including a motor 611 for driving the motor and a ball screw 612 connected to a rotation shaft of the motor 611.
A is fixedly arranged, and further, a driving mechanism 62A including a motor 621 for driving the mask mounting table 11 and a ball screw 622 connected to a rotation shaft of the motor 621 is fixedly arranged.

On the other hand, the substrate mount 39 has a ball screw 612.
It is coupled by screwing to and is driven in the x direction as shown in FIG. 5B as the ball screw 612 rotates. Similarly, the mask mounting table 11 is also coupled to the ball screw 622 by screwing, and is driven in the x direction as shown in FIG. 5B as the ball screw 622 rotates. In order to drive the substrate mounting table 39 and the mask mounting table 11 so that the image of the mask 1 is accurately imaged on the substrate 3 by the imaging optical system 5, the imaging optical system 5 is shown in FIG. As shown, it is an inversion optical system and the magnification is M. Therefore, the driving of the substrate mounting table 39 and the mask mounting table 11 is opposite to each other, and the driving speed of the substrate mounting table 39 is set to Vs, and the mask mounting is performed. When the drive speed of the table 11 is Vm, there is a relationship of Vs = -MVm.

Therefore, the mask 1 and the substrate 3 are installed on one rotary stage 41A, and on this rotary stage 41A, the drive mechanism 61A and the drive mechanism 62A are independently driven in one axial direction (x direction). The rotary stage 41A is arranged so as to rotate in a direction indicated by an arrow around a rotation center of a rotary shaft 43 provided on a straight line connecting the mask 1 and the substrate 3. The lens 51 in the imaging optical system 5 has a magnification M>
An erecting image lens of 0 is used. In FIG. 6, the positional relationship between the light irradiation region 11 on the mask 1 and the light irradiation region 31 on the substrate 3 is as follows: the distance from the center of the region 11 to the rotation center is a, and the distance from the center of the region 31 to the rotation center is b. Then, M = b / a is satisfied.

Next, the operation will be described with reference to FIG.
In FIG. 6, the mask 1 is irradiated with the laser beam 22 perpendicularly to the paper surface from below the paper surface. The area to be irradiated is the area 11 shown by the shaded area in the mask 1 as shown in FIG. The light applied to the mask 1 is
After passing through the opening of the mask 1, it is transferred onto the substrate 3 by the imaging optical system 5 shown in FIG. 5 and processed. The processed region on the substrate 3 is a region 31 shown by hatching on the substrate 3 in FIG. In this state, the rotary stage 41A
6 is rotated about the rotation axis 43, the laser beam irradiates the mask-shaped region 12 on the mask 1 as shown in FIG.
2 will be processed.

Next, the mask 1 and the substrate 3 are driven at respective speeds a and b to the center of rotation at a speed ratio equal to the magnification M,
The unprocessed area is sequentially processed. At this time, the order of irradiating the mask 1 with the laser light and the order of processing the substrate 3 are as follows: a, b, c, and d, as shown in FIGS. 7 (a) and 7 (b), respectively. Be seen.

According to such a method, with respect to driving in the rotation direction, the mask 1 and the substrate 3 have the same rotation stage 4
Since they are mounted on 1A at the same time, it is possible to perform processing in which drive synchronization between the mask 1 and the substrate 3 does not occur in principle.

Usually, the synchronization of the stages is easy if only the alignment is performed, but it is difficult to maintain the accuracy in the speed control when continuously driving. Therefore, continuous drive requiring speed control is dealt with by mechanical rotation as in this embodiment, and separate drive systems for the mask 1 and the substrate 3 are used for step movement. The device of this embodiment can be driven at an arbitrary speed ratio while maintaining the accuracy during continuous driving.

Further, in the above embodiment, the mask 1 and the substrate 3
, And the case where they are driven by separate drive mechanisms 61A and 62A, respectively. As shown in FIG. 8, a ball screw of pitch A is used for the mask 1 and a ball screw of pitch B is used for the substrate 3, respectively. However, it is also possible to use a drive mechanism 63A in which those two ball screws are connected and one ball screw 631 is driven by the motor 63. With such a configuration, since the driving is always performed in synchronism with each other, the synchronous deviation does not occur in the synchronous driving.

Generally, a mass production processing apparatus requires a positioning mechanism for the substrate 3. Therefore, the configuration described in FIGS. 9 to 11 is a step further than the configuration in FIG. 5 to have a positioning mechanism. In FIG. 9, the substrate 3 is the mask 1 and the substrate 3.
On the holding stage 41A on which the object is placed is mounted on the stage 39 which can be driven in one axis direction.
If the substrate 3 is not installed at an accurate position on the stage 39 as shown in FIG. 2, laser light is irradiated to the central position in the vertical direction on the paper surface of the mask 1 (region 1).
At the time of 1), there occurs a processing displacement such that the edge of the substrate 3 is processed on the corresponding substrate 3 (region 31). This is the center of the mask 1, the center of the substrate 3 and the rotation axis 4
The cause is that the center of 3 is not aligned in a straight line.

In the structure of the present invention, in addition to the configuration of FIG. 5, as shown in FIGS. 9 to 11, the holding stage 41A is rotated relative to the rotation shaft 43 in a uniaxial direction (y) orthogonal to the aforementioned uniaxial direction (x direction). The driving mechanism 44 for driving in the direction) is provided. The drive mechanism 44 includes a motor 46 having a ball screw 45 fixedly arranged on the stage 41A.
And a joint 46 screwed to the ball screw 45 and fixed to the tip of the rotary shaft 43. In such a configuration, when the processing region 31 of the substrate 3 is displaced as shown in FIG. 10, the drive mechanism 44 is driven as shown in FIG. 11, and the holding stage 41A is driven with respect to the rotation shaft 43. be able to.

As a result, the center of rotation 43 of the holding stage 41A, the center of the mask 1 and the center of the substrate 3 are aligned on a straight line, so that the processing misalignment can be adjusted. This positional deviation adjustment is only in the vertical direction of the paper surface in the figure, but for the horizontal adjustment, the mask 1 and the substrate 3 are provided with drive mechanisms 62A and 61A, respectively. It is possible.

(Embodiment 5) FIG. 12 is a view for explaining the configuration of an optical processing apparatus according to another embodiment of the present invention.
In this embodiment, the mask 1 and the substrate 3 are respectively mounted on the stage 64 and the stage 65 which are freely driven in the XY directions. In this state, the mask 1 and the substrate 3 are connected by a connecting pantograph 66 having a fulcrum 66a and a joint 66b which are driven at a ratio a / b.

According to such a configuration, the mask 1 and the substrate 3 can be driven at any speed ratio a / b by arbitrarily driving the mask 1 or the substrate 3, whereby the above-described embodiment can be realized. As in Examples 1 to 4, a large area can be processed with a small laser beam.

[0026]

As described above, according to the present invention, in a laser processing apparatus for processing by synchronously driving a mask and a substrate, it is possible to enhance the synchronous driving accuracy between the mask and the substrate. The laser processing can be realized with higher accuracy. Further, since a synchronous drive device for synchronously driving the mask and the substrate is not required, an extremely excellent effect such as improvement in processing accuracy and reduction in device cost can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration according to an embodiment of a laser processing apparatus according to the present invention.

FIG. 2 is a perspective view showing an example of the image forming optical system of FIG.

FIG. 3 is a sectional view showing the configuration of another embodiment of the laser processing apparatus according to the present invention.

FIG. 4 is a cross-sectional view showing a configuration of a laser processing apparatus according to still another embodiment of the present invention.

FIG. 5 is a cross-sectional view showing the configuration of another embodiment of the laser processing apparatus according to the present invention.

FIG. 6 is a diagram for explaining the operation of the configuration of FIG.

FIG. 7 is a diagram for explaining the operation of the configuration of FIG.

FIG. 8 is a plan view showing the configuration of another embodiment of the laser processing apparatus according to the present invention.

FIG. 9 is a sectional view showing the configuration of another embodiment of the laser processing apparatus according to the present invention.

FIG. 10 is a plan view illustrating the operation of the configuration of FIG.

FIG. 11 is a plan view illustrating the operation of the configuration of FIG.

FIG. 12 is a plan view showing the configuration of another example of the laser processing apparatus according to the present invention.

FIG. 13 is a perspective view showing a configuration of an optical processing device proposed by the inventors.

[Explanation of symbols]

 1 mask 12 area where light is collectively irradiated on the mask 2 laser light imaged on the substrate 21 laser light transmitted through the mask 22 laser light irradiated on the mask 3 processed substrate 32 on processed substrate Area to be processed in batch 39 Stage for mounting substrate to be processed 41 Mask and substrate holding stage 42 Connecting rod 43 Rotation axis 43A Drive mechanism 44 Drive mechanism 45 Ball screw for driving holding stage 46 Motor for driving ball screw 47 Ball screw and rotation Joint 5 for coupling with shaft 5 Imaging optical system 51 Imaging lens 52 Reflecting mirror 53 Reflecting mirror 54 Reflecting mirror 55 Reflecting mirror 61A Drive mechanism 611 Drive motor 612 Ball screw 621 Drive motor 622 Ball screw 62A Drive mechanism 631 Ball screw 63A Drive mechanism 64 X -Y stage 65 XY stay 66 consolidated pantograph 66a fulcrum 66b joint 7 mirror

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location H05K 3/00 K 6921-4E // B23K 101: 42 (72) Inventor Masao Izumo 8 Tsukaguchihonmachi, Amagasaki City, Hyogo Prefecture 1-chome Sanritsu Electric Co., Ltd. Itami Works

Claims (6)

[Claims] 1. A mask having a light transmitting portion that transmits light from a light source and an opaque portion that does not transmit the light, and light passing through the mask has an image plane on a plane including the mask. An image forming optical system for forming an image, and a laser processing device. 2. A mask having a light transmitting portion that allows light from a light source to pass therethrough and an opaque portion that does not allow the light to pass therethrough, and a pedestal for mounting a workpiece on the same plane as the mask. An image forming optical system for forming an image of the light passing through the mask so as to have an image plane on a plane of the workpiece, a laser processing apparatus. 3. A mask having a light transmitting portion that allows light from a light source to pass therethrough and an opaque portion that does not allow the light to pass therethrough, and a pedestal on which a workpiece is placed on the same plane as the mask. A drive mechanism that rotates the gantry in a uniaxial direction about a rotation axis that is perpendicular to the plane, and an image that forms the light that has passed through the mask so that it has an image plane on the plane of the workpiece. A laser processing device comprising: an optical system. 4. A mask having a light transmitting portion that allows light from a light source to pass therethrough and an opaque portion that does not allow the light to pass therethrough, and a pedestal for mounting a workpiece on the same plane as the mask. A first drive mechanism and a second drive mechanism for driving the gantry parallel to a biaxial direction orthogonal to each other on a plane parallel to the plane; and an image of the light passing through the mask on the plane of the workpiece. An image forming optical system for forming an image so as to have a surface, and a laser processing device. 5. A mask having a light transmitting portion that transmits light from a light source and an opaque portion that does not transmit the light, a first XY stage on which the mask is mounted, and the same plane as the mask. Second X on which the work piece is placed
-Y stage, a coupling mechanism that stretchably couples the first XY stage and the second XY stage, and an image plane of the light passing through the mask on the plane of the workpiece. An image forming optical system for forming an image so that the laser processing apparatus is provided. 6. A mask having a light transmitting portion that transmits light from a light source and an opaque portion that does not transmit the light, and the workpiece and the workpiece to be movable in parallel on a plane different from the mask. A laser processing apparatus comprising: a connecting rod to be mounted; and an image forming optical system that forms an image of light that has passed through the mask so as to have an image plane on a plane of the workpiece.