KR20100088874A - A method of exposing a pcb and a method of manufacturing a pcb comprising the same - Google Patents

Abstract

PURPOSE: A PCB(Printed Circuit Board) exposing method and a manufacturing method of a PCB including the same are provided to accurately measure the amount of deformation generated from a base substrate by forming an external align mark and an internal align mark, respectively. CONSTITUTION: A plurality of external align marks(110, 130, 150, 170) and a base substrate(100) having the internal align mark(200) are provided. The external align mark is formed on the external peripheral part. The internal align mark is formed on the inner side of a virtual closed loop which connects the nearby external align marks. The amount of deformation of the base substrate is calculated by comparing a relative position between the external align marks and a relative position between the external align mark and the internal align mark.

Description

A method of exposing a printed circuit board and a method of manufacturing a printed circuit board including the same {A METHOD OF EXPOSING A PCB AND A METHOD OF MANUFACTURING A PCB COMPRISING THE SAME}

The present invention relates to a method of manufacturing a printed circuit board, and more particularly, to an exposure method of a printed circuit board and a method of manufacturing a printed circuit board including the same.

With the development of the electronic industry, the demand for high functionalization and miniaturization of electronic components is increasing rapidly. In order to cope with this trend, printed circuit boards must also be miniaturized, and accordingly, a high density of circuit patterns is required.

Printed circuit boards have been multilayered to satisfy the needs of such small high density printed circuit boards, and the multilayer printed circuit boards are electrically connected by vias that electrically connect the respective layers. The via is formed through the insulating layer and is electrically connected to the specific circuit pattern of each circuit layer.

At this time, in order for the circuit layers arranged up and down to be electrically connected through the connection passages called vias, the matching of the upper and lower circuit layers must be precise. If the matching error is large, defects such as the via not connecting to the circuit layer occur.

This is because the problem of interlayer matching of printed circuit boards, which includes not only the problem of matching the circuit layer with the vias but also the problem of matching the connection pads formed in the outermost part of the printed circuit board and the opening of the solder resist layer exposing the same, It is a big problem in manufacturing.

This problem is intimately connected with the exposure process for patterning the components formed on the printed circuit board. The exposure process is one of the processes for forming circuit patterns, vias, and open holes formed on a printed circuit board to have a specific pattern. It is a process that changes from the unirradiated part. Since the positions of circuit patterns, vias, opening holes, etc., which are substantially formed in the printed circuit board are determined in this exposure process, precise matching in the exposure process is required.

Efforts have been made to reduce such exposure errors, but even if the exposure equipment is precisely controlled, the printed circuit board has a limit in reducing the exposure process error due to the deformation of its shape during the manufacturing process.

1 to 2 schematically illustrate a process of performing an exposure process in consideration of the amount of deformation generated in the manufacturing process of a printed circuit board according to the prior art.

Referring to FIG. 1, a printed circuit board 10 having first to fourth alignment marks 11, 13, 15, and 17 formed thereon is provided. The alignment marks 11, 13, 15, and 17 are formed at the outer edges of the printed circuit board 10 and used to measure the appearance change of the printed circuit board 10. For example, the distance between the alignment marks 11, 13, 15, and 17 before performing the insulation layer deposition process on the printed circuit board 10 and the alignment marks 11, 13, 15, and 17 after the deposition process. By comparing the distance between the measured change amount of the printed circuit board 10 can be measured.

When the change amount of the printed circuit board 10 is measured, as shown in FIG. 2, the change amount generated in the printed circuit board is reflected in the mask 20 used in the exposure process. That is, the mask 20 is scaled so that the alignment marks 21, 23, 25, and 27 formed on the mask 20 correspond to the alignment marks 11, 13, 15, and 17 of the printed circuit board.

Thereafter, the alignment marks of the mask 20 and the printed circuit board 10 are aligned by the CCD 30 and the exposure process is performed.

However, since the deformation of the printed circuit board is caused by various factors such as thermal, physical, and chemical factors, the deformation is nonlinear, and when only the alignment mark formed on the outer edge of the printed circuit board is measured, the exposure mask is measured. Even if reflected in the error was too large a problem.

The present invention was created to solve the problems of the prior art as described above, an exposure method that can accurately measure the amount of deformation generated in the printed circuit board during the manufacturing process to reflect the change in the scale of the exposure mask and the printing comprising the same We propose a method for manufacturing a circuit board.

The exposure method of the printed circuit board according to the present invention includes (A) an inner alignment mark formed inside a virtual closed loop in which a plurality of outer alignment marks formed on an outer edge portion and the outer alignment marks adjacent to each other are linearly connected. Providing a base substrate having a; (B) calculating a deformation amount of the base substrate by comparing the relative position between the outer alignment marks and the relative position between each of the outer alignment marks and the inner alignment marks with reference data before deformation; (C) applying an amount of deformation of the base substrate to provide an exposure mask having a deformed scale; And (D) performing an exposure process on the base substrate using the exposure mask.

As a preferable feature of the present invention, the exposure mask is one of Gerber data.

The method of a printed circuit board according to the present invention is characterized by including the exposure process described above.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to the exposure method of the printed circuit board and the manufacturing method of the printed circuit board including the same according to the present invention, the outer alignment mark formed on the outer edge portion of the base substrate for manufacturing the printed circuit board and the inner aligning formed inside the base substrate Including the mark, the exposure mask also includes alignment marks corresponding to the alignment mark formed on the base substrate, it is possible to accurately measure and reflect the amount of deformation occurred in the base substrate, which can greatly reduce the process error of the exposure process There is an advantage.

Hereinafter, a preferred embodiment of an exposure method of a printed circuit board and a method of manufacturing a printed circuit board including the same according to the present invention will be described in detail with reference to the accompanying drawings. Throughout the accompanying drawings, the same or corresponding components are referred to by the same reference numerals, and redundant descriptions are omitted. In this specification, terms such as top and bottom are used to distinguish one component from another component, and a component is not limited by the terms.

3 to 5 are views illustrating a method of exposing a printed circuit board and a method of manufacturing a printed circuit board including the same according to a preferred embodiment of the present invention in the order of process.

First, as shown in FIG. 3, the plurality of outer alignment marks 110, 130, 150, and 170 formed on the outer edge portion and the outer alignment marks 110, 130, 150, and 170 adjacent to each other are connected in a straight line. It is a step of providing a base substrate 100 having an inner alignment mark 200 formed inside a virtual closed loop.

Printed circuit boards are used for component mounting and wiring of electronic devices. A printed circuit board is formed by etching metal on the insulating layer according to the wiring pattern (removing it by leaving only the circuit on the wire and removing it). ; PCB). The circuit board may be a single-sided PCB in which wiring is formed only on one side of the insulating board, a double-sided PCB in which wiring is formed on both sides, and an MLB (Multi Layered Board) that is wired in multiple layers.

In manufacturing such printed circuit boards, for example, mechanical (physical) and chemical processes such as via hole processing, metal etching or plating processes, insulating layers or metal foil lamination processes are involved, and thermal, physical and chemical actions occurring in these processes The original plate 100a (see FIG. 4) used as a material is deformed during the manufacturing process.

The term base substrate 100 is used herein to mean an intermediate product that occurs at an intermediate stage of printed circuit board manufacturing as described above. That is, the base substrate 100 is used to mean a substrate in which any deformation of the above-described series of printed circuit board manufacturing processes is performed. The base substrate 100 may be an insulating layer on which a circuit pattern is not yet formed, or may be a single-sided, double-sided or multilayer printed circuit board on which a circuit layer is already formed.

FIG. 4 illustrates a disc 100a in a state before the base substrate 100 shown in FIG. 3 is deformed. Here, the original plate 100a is used as a term referring to a state of a stage before the base substrate 100 is provided, and refers to a product generated at the beginning and middle stages of manufacturing a printed circuit board. The original plate 100a may also be an insulating layer made of an insulating resin, a single-sided or double-sided copper clad laminate (CCL), or a single-sided, double-sided or multilayer printed circuit board. As shown in FIG. 4, the original plate 100a is provided with an alignment mark indicating a reference position of a subsequent via hole processing, exposure / development, lamination, and circuit layer forming process.

Any one or two or more processes of a printed circuit board manufacturing process are performed on the master plate 100a to provide a base substrate 100. As described above, via hole processing, etching, or insulating layer is laminated on the master plate 100a. When such a process is performed, a shape deformation occurs in the master plate 100a such that the shape of the master plate 100a and the base substrate 100 and the positions of the respective components included therein do not completely match.

The base substrate 100 according to the present exemplary embodiment includes a plurality of outer alignment marks 110, 130, 150, and 170 formed on the outer edges of the base substrate 100 and the outer alignment marks 110, 130, adjacent to each other. And an inner alignment mark 200 formed inside an imaginary closed loop in which 150 and 170 are linearly connected. Here, the outer alignment marks 110, 130, 150, and 170 and the inner alignment marks 200 may be through holes, metal patterns, grooves, protrusions, or the like formed in the disc 100a.

Meanwhile, in FIG. 3, the outer alignment marks 110, 130, 150, and 170 are shown only at the corner vertex portions of the base substrate 100, but the present invention is not limited thereto. It will be appreciated that the outer alignment marks 110, 130, 150, 170 may also be formed in the central portion. In addition, in the present exemplary embodiment, one inner alignment mark 200 formed at the center of the base substrate 100 is described as an example, but the inner alignment mark 200 may be two or more, and the center of the base substrate 100 may be the same. It does not have to be located at.

Next, relative positions between the outer alignment marks 110, 130, 150, and 170 formed on the base substrate 100, and between the respective outer alignment marks 110, 130, 150, and 170 and the inner alignment mark 200. Computing the amount of deformation of the base substrate 100 by comparing the relative position of the with reference data before deformation.

The change in the relative position between the alignment marks formed on the base substrate 100 may be measured by comparing the relative positions between the alignment marks formed on the original plate 100a to determine the amount of change occurring in the base substrate 100. For example, the relative position between the alignment marks formed on the original plate 100a is the distance (a, b, c, d) between the outer alignment mark and the outer alignment mark, and the distance between the outer alignment mark and the inner alignment mark ( α, β, γ, ω) and the angle θ formed by the line connecting two alignment marks, and the like, are recorded in a storage medium such as a computer. Therefore, the relative position between the alignment marks formed on the base substrate 100, that is, the distance (a ', b', c ', d') between the outer alignment mark and the outer alignment mark, and the outer alignment mark, for example. The distance between the inner alignment marks (α ', β', γ ', ω'), and the angle (θ ') formed by the line connecting the two alignment marks is measured and compared with the data of the original plate 100a. The pattern of change can be seen more clearly.

In contrast to the original plate (100a), the change in the shape of the base substrate 100 is irregular without direction, so it is impossible to accurately measure the change occurring over the entire area of the base substrate 100, but the base substrate 100 according to the present embodiment Since the inner alignment mark 200 is further provided, it is possible to more accurately measure the amount of deformation generated inside the base substrate 100.

Next, as shown in FIG. 5, a step of providing an exposure mask 300 having a deformed scale by applying a deformation amount of the base substrate 100.

Here, the exposure mask 300 may be a glass mask having a light blocking pattern, a dry film having a light transmission hole, or the like, or a gerber acting as the exposure mask 300 in an LDI (Laser Direct Imaging) exposure apparatus. ) Can be data. An LDI exposure apparatus is a device that directly exposes an exposed layer on a substrate along a designated path by using a laser diode as a light source. Therefore, in the LDI exposure apparatus, since the exposure is performed along the path of the laser diode, Gerber data containing such path information may be referred to as an exposure mask 300.

Since the exposure mask 300 is used to perform an exposure process on the exposed layer formed on the base substrate 100, for example, a photosensitive dry film, a photosensitive insulating material, a photosensitive solder resist layer, and the like, the amount of deformation generated in the base substrate 100. It is important to have a calibrated scale. The exposure mask 300 according to the present exemplary embodiment may include the outer alignment marks 310, 330, 350, corresponding to the outer alignment marks 110, 130, 150, and 170 formed on the disc 100a and the base substrate 100. 370 and the inner alignment mark 400 corresponding to the inner alignment mark 200 formed on the disc 100a and the base substrate 100, and are corrected by the amount of deformation generated in the base substrate 100. That is, the exposure mask 300 used in the present embodiment may be provided by correcting the exposure mask 300 designed based on the original plate 100a by the amount of deformation generated in the base substrate 100. In this embodiment, since the exposure mask 300 further includes an inner alignment mark 400, it is possible to provide an exposure mask 300 that more accurately matches the base substrate 100. In this case, when the exposure mask 300 is Gerber data, the alignment mark formed on the exposure mask 300 may also be a data value defining the position of the alignment mark.

Next, an exposure process is performed on the base substrate 100 using the exposure mask 300. When the exposure mask 300 is provided, the exposure mask 300 is positioned on the base substrate 100 so that the alignment mark of the base substrate 100 and the alignment mark of the exposure mask 300 are aligned to perform exposure. The alignment mark may be arranged by, for example, an imaging device such as the CCD 500, a sensor such as an infrared sensor, and a combination thereof.

After the exposure process is completed, further processes such as a development process may be performed to complete the printed circuit board. This is done in a known manner, so detailed description thereof will be omitted here.

According to the exposure method of the printed circuit board and the manufacturing method of the printed circuit board including the same according to the present invention, the outer alignment marks 110, 130, formed on the outer edge portion of the base substrate 100 for manufacturing the printed circuit board 150 and 170 and an inner alignment mark 200 formed inside the base substrate 100, and the exposure mask 300 also includes alignment marks corresponding to the alignment marks formed on the base substrate 100. Since it is possible to accurately measure and reflect the amount of deformation generated in the base substrate 100, there is an advantage that can greatly reduce the process error of the exposure process.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Therefore, such modifications or variations will have to belong to the claims of the present invention.

1 to 2 schematically illustrate a process of performing an exposure process in consideration of the amount of deformation generated in the manufacturing process of a printed circuit board according to the prior art.

3 to 5 are views illustrating a method of exposing a printed circuit board and a method of manufacturing a printed circuit board including the same according to a preferred embodiment of the present invention in the order of process.

<Description of Major Symbols in Drawing>

100 Base plate 100a disc

300 exposure mask 500 CCD

Inside alignment mark on the 200 base substrate

Inside alignment mark of 400 exposure mask

Outer alignment mark on 110, 130, 150, 170 base board

Outside alignment mark of 310, 330, 350, 370 exposure mask

Claims (3)

(A) providing a base substrate having a plurality of outer alignment marks formed on the outer edge portion and the inner alignment mark formed inside the virtual closed loop linearly connecting the outer alignment marks adjacent to each other; (B) calculating a deformation amount of the base substrate by comparing the relative position between the outer alignment marks and the relative position between each of the outer alignment marks and the inner alignment marks with reference data before deformation; (C) applying an amount of deformation of the base substrate to provide an exposure mask having a deformed scale; And (D) performing an exposure process on the base substrate using the exposure mask; Exposure method of a printed circuit board comprising a. The method of claim 1, The exposure mask is a method of exposure to a printed circuit board, characterized in that the Gerber data (Gerber data). In the manufacturing method of a printed circuit board comprising a circuit layer and an insulating layer for transmitting an electrical signal formed on the insulating layer, A method of manufacturing a printed circuit board comprising the exposure process according to claim 1.

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