JP2002316286A - Method for correcting hole position in laser beam machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hole position correcting method that makes high precision correction possible for shrinkage or the like of a substrate caused by heat treatment in other process and that is particularly useful in a high-density circuit board. SOLUTION: The hole position correcting method in a laser beam machining device is characterized by using a workpiece which is formed with an insulating material 8 enabling the lower face of the workpiece to be recognized from the upper face with a picture recognizing means, providing a lower land 6 at a drilling position on the lower face of the workpiece, recognizing the land 6 in the entire machining area as a reference position mark from the upper face with the picture recognizing means to fetch as the picture data, and thus correcting the hole drilling data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus in which a through hole or a via hole is provided in a printed circuit board, particularly a printed circuit board, which requires a high density and high precision. The present invention relates to a method of correcting a hole processing position in a laser processing apparatus that corrects a contraction of a substrate due to a laser beam.

[0002]

2. Description of the Related Art To accurately process through holes or via holes in a high-density wiring circuit board, it is necessary for a processing apparatus to accurately recognize a position where a hole to be processed in a substrate to be processed is to be formed.

[0003] However, as the density of the substrate increases, the position of the hole to be drilled needs to be recognized with higher precision. Therefore, the shrinkage amount of the substrate to be processed changes due to the heat treatment received in another process. The influence cannot be neglected. As shown in FIG. 1, a reference position mark is provided on the workpiece, and the amount of change is calculated and corrected.

[0004] A conventional method for calculating and correcting a variation will be described below with reference to FIG. In FIG. 1, reference numeral 1 denotes a workpiece before contraction due to heat treatment, 2 denotes a workpiece after contraction, 3 denotes a reference position mark provided on the workpiece, and x and y denote workpieces before contraction. Reference position mark 3 on object 1
Length between, x _1, y ₁ is the length between the reference position mark 3 in the workpiece 2 after shrinkage.

When the variation is calculated by the above-described conventional method, the lengths x and y between the reference position marks 3 of the workpiece 1 before contraction due to the heat treatment are obtained in advance, and the workpiece 2 after contraction is obtained. The lengths x ₁ and y ₁ between the reference position marks 3 are obtained by image recognition means or the like, whereby the shrinkage coefficient in the x direction is x ¹ / x, and the shrinkage coefficient in the y direction is y ¹ / y. This is input to the hole processing data, and by multiplying the hole position processing data stored in advance by a shrinkage coefficient, the amount of fluctuation due to heat shrinkage or the like is corrected to correct the hole position.

[0006]

As described above, in the conventional hole position correcting method, the length between the reference position marks provided on the workpiece is measured so that the workpiece is shrunk by heat treatment received in another process. The amount of shrinkage is calculated based on the shrinkage amount, and the hole position is corrected by multiplying the shrinkage coefficient by the hole position processing data.

However, since the amount of shrinkage due to heat treatment applied to the workpiece in another process is non-linear, and it is necessary to perform accurate correction in units of μm, as shown in FIG.
A large number of reference position marks are provided on a workpiece, and a complicated calculation method corresponding to a non-linear shape has been used as a calculation method for hole position correction.

However, it is very difficult to optimally arrange the reference position marks on the workpiece in order to correct the amount of shrinkage with high accuracy in units of μm, and a large number of reference position marks are provided on the workpiece. This becomes a dead space when a circuit is formed on the substrate, which not only reduces the area that can be used on the workpiece, but also hinders high density.

In addition, it is necessary to adopt an operation method corresponding to the non-linear type, the operation becomes complicated, and much time is required for the operation.

[0010]

A via hole or a through hole is provided for electrically connecting a printed layer and a substrate. The via hole or the through hole is used for forming an electric circuit on a workpiece. The land of the conductive pair portion is formed at the position where the hole is formed.

The present invention has been made in view of this configuration. The object to be processed is formed of an insulating material whose lower surface can be recognized from the upper surface by the image recognition means. In addition to providing the land, the image recognition means recognizes the lower land in the entire processing area from the upper surface of the workpiece, captures the land as image data, and corrects the hole processing data.

According to the present invention, a land provided on the lower surface of a workpiece is used as a reference position mark,
The reference position mark does not become a dead space for forming a circuit, and the processing data and the land position are checked at all the hole processing positions. The position can be corrected, and a hole position correction method particularly effective for a high-density circuit board can be provided. Further, since all the lands are confirmed by the image recognizing means, defects in the land shape can be inspected before drilling.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION
A hole position correcting method in a laser processing apparatus including an image recognition unit that recognizes a land position of a workpiece and corrects hole processing data and a laser processing unit that performs a hole punching process at a hole punching position of the workpiece. Then, using a workpiece formed of an insulating material whose lower surface can be recognized from the upper surface of the workpiece by the image recognizing means, providing a land at a hole drilling position on the lower face of the workpiece, The land on the entire processing area is recognized as a reference position mark from the upper surface of the object, captured as image data, and the hole processing data is corrected. Since the dead space on the object is reduced and the processing data and land position are confirmed at all the hole processing positions, the hole position is more accurate than the conventional method. Can be corrected and the density can be increased, so that a particularly effective hole position correction method can be provided on a high-density circuit board. It has the effect of being able to perform an inspection before.

According to a second aspect of the present invention, a hole is drilled based on the corrected hole drilling data, and after the hole drilling, the reference position mark and the drilled hole shape in the entire area of the drilling rear are recognized, and all drilling states are recognized. By inspecting the workpiece after hole machining again by the image recognition means, it is possible to confirm the machining state of all holes in the workpiece. It has the effect of improving product accuracy.

According to a third aspect of the present invention, there is provided a laser processing apparatus using the hole position correcting method according to the first aspect, wherein the measuring stage includes image recognition means for recognizing a reference position mark over the entire workpiece. , A processing stage having a laser processing means is provided separately, and a reference position mark can be recognized on a measurement stage and a hole processing can be performed on the processing stage in parallel. At the same time, the next workpiece is transported to the measurement stage. Recognition and hole drilling operations are performed simultaneously in both stages, reducing measurement time loss and improving productivity. Has the effect of enabling

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. 3A and 3B show a step of forming a via hole on the substrate from an insulator which is a workpiece, (a) shows a state before drilling, (b) shows a state in which a via hole is formed at a land position by drilling, ( c) shows a state in which the upper land is provided after the drilling. In the figure, reference numeral 6 denotes a lower land provided at a hole processing position on the lower surface of an insulator 8, 6 'an upper land provided on a via hole 7, 7 a via hole, and 8 an insulator which is a workpiece. And the like, the lower land 6 provided on the lower surface of the insulator from the upper portion of the insulator.
Is formed of a material that can be recognized.

For example, a polyimide resin sheet is suitable. The via hole 7 is provided for electrically connecting the layers of the printed board, and is provided with an insulator (substrate) 8.
In order to form an electric circuit, lands 6 and 6 'are provided at positions where the via holes 7 are formed.

In the present embodiment, the lower land 6 provided on the lower surface of the insulator 8 is used as a reference position mark.
In FIG. 3, as shown in FIG. 3A, a lower land 6 is provided in advance on the lower surface of a hole processing position of an insulator 8 made of, for example, a polyimide resin sheet, and the upper surface of the insulator 8 is image-recognized by a licensor or the like. Thus, the lower land 6 in the entire processing area is recognized as a reference position mark, this is taken into image data, the hole processing position is corrected based on this data, and then the hole processing is performed at the hole processing position by laser processing means. To form a via hole 7 on the lower land 6. Next, the upper land 6 is formed on the via hole 7 if necessary.

FIG. 4 schematically shows a laser processing apparatus according to an embodiment of the present invention. In FIG. 4, reference numeral 9 denotes a measurement stage for measuring a land, 10 denotes a laser beam irradiated to a predetermined position of the substrate, and a hole is formed on the substrate. A laser processing stage for processing, 11 a laser oscillator, 12 a laser optical system including a laser oscillator 11, a galvanometer mirror 12a,
3 is a position recognition camera, and 14 is a line sensor as image recognition means.

In the laser processing apparatus of the present embodiment,
The measurement stage 9 and the processing stage 10 are provided in a pair of left and right forms so that two workpieces can be measured or processed at the same time. On the measurement stage 9, the workpiece is scanned in one direction, and the lower land 6 provided on the lower surface of the workpiece (see FIG. 3) from the upper surface of the workpiece by the licensor 14 disposed above the workpiece. Is recognized in all the areas, the respective land positions are determined, and the hole machining data is corrected based on this data. Next, the workpiece is transported to the laser processing stage 10, the holding position of the workpiece is corrected by the reference position recognition camera 13 on the processing stage 10, and laser processing is performed based on the corrected hole position data. At the same time that the workpiece is transported to the processing stage 10, the next workpiece is transported to the measurement stage 9, and the lands in the entire area of the next workpiece are detected and the position of each land is determined. repeat. By adopting such a method, it is possible to detect a land in all areas and reduce a loss of measurement time for determining a land position.

Further, by forming the measuring stage 9 and the processing stage 10 as a pair of left and right so that two workpieces can be processed at the same time, a laser processing apparatus with high productivity can be provided.

Further, by inspecting the workpiece after drilling again at the inspection stage, it is possible to confirm all drilling states after drilling.

[0023]

According to the present invention, the dead space on the workpiece can be reduced by using the land provided on the lower surface of the workpiece as the reference position mark. To confirm
Effective hole position in high-density circuit boards, which enables more reliable and highly accurate hole drilling than conventional methods that use the reference position mark for correction, resulting in product failure even if one hole position accuracy is not satisfied. A correction method can be provided.

Further, since the lands at all points are confirmed by the image recognizing means, defects in the land shape can be inspected before drilling holes.

[Brief description of the drawings]

FIG. 1 is a diagram comparing changes before and after contraction of a workpiece with reference position marks (XY directions). (A) Workpiece before shrinkage (b) Workpiece after shrinkage

FIG. 2 is a diagram when a large number of reference marks are provided on a workpiece.

FIG. 3 is an enlarged sectional view showing a step of providing a via hole on a substrate. (A) shows a state before drilling (b) shows a state where via holes are provided at land positions (c) shows a state where upper lands are provided after drilling

FIG. 4 is a schematic configuration diagram of a laser processing apparatus to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Workpiece before deformation 2 Workpiece after contraction 3 Reference position mark on workpiece 4 Workpiece 6 Lower land 6 'Upper land 7 Via hole 8 Insulator 9 Measurement stage 10 Processing stage 11 Laser oscillator 12 Laser Optical System 12a Galvano Mirror 13 Reference Position Recognition Camera 14 Line Sensor

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Izumi Nakai 1006 Kadoma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (72) Inventor Takeshi Muneyuki 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 4E068 AF00 CA17 CC02 DA11

Claims (3)

[Claims] 1. A laser processing apparatus comprising: an image recognition unit that recognizes a land position of a workpiece and corrects hole processing data; and a laser processing unit that performs a drilling process at a drilling position of the workpiece. A hole position correcting method, comprising: using a workpiece formed of an insulating material whose upper surface can be recognized from the upper surface of the workpiece by an image recognizing means; A land position correction method for a laser processing apparatus, comprising: recognizing a land in the entire processing area from a top surface of a workpiece as a reference position mark, capturing the land as image data, and correcting the hole processing data. 2. The method according to claim 1, wherein a hole is drilled based on the corrected hole drilling data, and after drilling, a reference position mark of the entire drilling area and a drilled hole shape are recognized, and all drilling states are confirmed. The hole position correcting method in the laser processing apparatus according to claim 1. 3. A laser processing apparatus using the hole position correction method according to claim 1, wherein the measurement stage includes an image recognition unit for recognizing a reference position mark of the entire workpiece, and the processing includes a laser processing unit. A laser processing apparatus characterized in that a stage is provided separately, and a reference stage mark can be recognized on a measurement stage and a drilling process can be performed on a processing stage in parallel.