KR100433828B1 - Film-type insulating material for preparing PCB by build-up process - Google Patents

Abstract

The present invention relates to an insulating material in the form of a film for manufacturing a PCB by a build-up method, and more particularly, to minimize the plating thickness deviation and to maintain a constant insulation thickness when forming an insulating layer in the process of manufacturing a PCB by the build-up method. It relates to an insulating material in the form of a film that can be made. The film-type insulating material according to the present invention is a film-type insulating material consisting of a cover film, a film for forming an insulating layer and a mylar film, wherein the film for forming the insulating layer is 1 to 10mm wider than the cover film is located at the top It is formed as small as possible, and a flow preventing jaw having {(height of the insulating layer forming film) × (width of 1 to 10mm)} is formed at both ends of the cover film, or {(at the both ends of the insulating layer forming film layer). A flow preventing dam having a height of the insulating layer forming film) x (a width of 1 to 10 mm) is manufactured and placed so that the resin of the insulating layer forming film does not flow out.

Description

Film-type insulating material for preparing PCB by build-up process}

The present invention relates to an insulating material in the form of a film for manufacturing a PCB by a build-up method, and more particularly, to minimize the plating thickness deviation and to maintain a constant insulation thickness when forming an insulating layer in the process of manufacturing a PCB by the build-up method. It relates to an insulating material in the form of a film that can be made.

With the development of the electronics industry, the electronic components industry is also rapidly developing and gradually changing to miniaturization and multifunction. In the case of a personal portable terminal, the Internet has a complex function such as an internet connection function and a video function, so that the expansion of memory capacity is inevitable, and the emergence of a miniaturized package is inevitable.

In the conventional method of manufacturing a multilayer printed circuit board, a plurality of prepreg sheets, which are staged by impregnating an epoxy resin in a glass fabric as an insulating adhesive layer on a substrate on which an inner layer circuit is formed, are laminated and pressed into a through-hole. Has been used to conduct interlayer conduction. However, this method has a problem such as requiring a large-scale facility and a long time. As a method for solving the above problem, a buildup method of alternately stacking an organic insulating layer on a conductor layer of a substrate on which an inner layer circuit is formed has been proposed.

In the method of manufacturing a multilayer printed circuit board according to the build-up method, after forming an inner layer circuit on a substrate, a method using an RCC method for laminating an insulating material coated with copper foil, or coating a liquid insulating material through a printing method The method of laminating an insulating material has been used typically. In particular, the RCC method, which has been used since the beginning of the development of the build-up method, cannot control the flowability of the insulating material due to the temperature and pressure of the press used when laminating the insulating material. Therefore, it maintains a semi-hardened state, and thus, in forming the circuit after the build-up, there is a problem in forming a dense pattern by the copper foil thickness, and also has a problem in forming a lot of patterns when machining a hole using a drill. In addition, since the defects occur not only on the insulation distance but also on the surface of the copper foil by the processed holes, there is a problem of filling the processed holes with other resins. Therefore, in order to solve this problem, a build-up method for coating and forming a liquid insulating material by a printing method has been commercialized. The printed circuit board was manufactured by forming an inner layer circuit on a substrate, printing a liquid insulating material, forming a hole with a drill, plating, drying, and forming a circuit again. As such, when the build-up product is manufactured by printing the liquid insulating material, a problem is generated by the conventional RCC lamination method because the circuit is formed again after panel plating on the surface of the coated insulating material. However, since the liquid insulating material is coated by the printing method, the amount of the insulating material applied on the upper and lower surfaces of the product is not constant, resulting in a deviation of the insulation distance, which causes warpage of the product. In addition, when there is a hole in the product, the problems caused by the RCC lamination method are the same unless the hole is filled with another resin. In addition, since the handling of the product after the application of the insulating material is difficult to produce a lot of defects, because both sides of the product can not be applied at the same time there is a problem that the manufacturing cost of the product increases the number of processes.

What was developed to solve this problem is to apply a method of forming an insulating layer using an insulating material in the form of a film in the manufacture of a printed circuit board. For example, Japanese Patent Application Laid-Open No. 8-64960 applies an adhesive, dries it, attaches a film-like additive adhesive, heats it, roughens it with an alkaline oxidant, and forms a conductor layer by plating to manufacture a multilayer printed circuit board. Japanese Laid-Open Patent Publication No. 7-202418 describes a method of manufacturing a multilayer printed circuit board by pasting an adhesive layer copper foil having an adhesive layer formed of a high molecular weight epoxy resin and a liquid epoxy resin on a copper foil to an inner layer circuit board. It is. In addition, Japanese Laid-Open Patent Publication No. 11-97927 discloses an interlayer adhesive film for multilayer printed circuit boards which can simultaneously perform resin filling in the inner layer circuit pattern and in the surface via hole and / or through hole at the same time. .

As shown in Figure 1, the general film-like insulating material is an insulating film for forming an insulating layer made of a resin and a cover film (cover film) is laminated on the top to protect the insulating material and a mylar like a release film on the bottom A film (mylar film) is laminated, wound and stored in a roll shape, and the insulating material stored in the roll shape is cut along the XY line of FIG.

When the film-type insulating material of the above configuration is vacuum laminated under heating and pressing conditions, due to the thermal fluidity characteristics of the insulating material, there is a problem that the insulating material is infiltrated at the end of the film to contaminate the press surface or laminate roll. In addition, due to excessive flow of the insulating layer around the outer periphery of the substrate, the thickness difference of the insulating layer occurs, and when the plating proceeds after laminating the insulating layer, the clamping position for the plating is etched on the resin rather than the copper foil, and current distribution occurs. Since there is a problem that causes the plating thickness deviation.

Therefore, the present invention solves the conventional problems, even when vacuum-laminated under heating and pressurized conditions, the insulating material does not leak from the distal end of the film, so as not to contaminate the press surface or laminate roll, to uniform the thickness of the insulating layer, the current during the plating progress It is to provide a film-type insulating material that can protect the outer copper foil from the resin so that the plating thickness is uniform by improving the distribution and the plating clamp is correctly connected to the plating during horizontal plating.

Insulating material of the film form according to the present invention for achieving the above object is a film of an insulating material consisting of a cover film, the film for forming an insulating layer and the mylar film, the cover film for the insulating layer forming is located on the top It is formed smaller by a width of 1 to 10mm, and a flow preventing jaw having {(height of the insulation layer forming film) × (width of 1 to 10mm)} is formed at both ends of the cover film, or for forming the insulation layer. The film is formed to be smaller by a width of 1 to 10 mm than the cover film located above, and has {(height of the film for forming the insulating layer) × (width of 1 to 10 mm)} at both ends of the film layer for forming the insulating layer. Producing and positioning the flow preventing dam is characterized in that it is manufactured so that the resin of the insulating layer forming film does not flow out.

1 is a side cross-sectional view showing a cross section of a conventional film-shaped insulating material,

Figure 2 is a side cross-sectional view of the insulating material of the film form according to the present invention,

3 is a side cross-sectional view of another film-type insulating material according to the present invention.

Explanation of symbols on the main parts of the drawings

1, 10: cover film, 2, 20: film for forming an insulating layer

3, 30: mylar film, 40: flow preventing dam

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

2 and 3 are side cross-sectional views of the insulating film in the form of a film according to the present invention, the cover film (1, 10), insulating material resin for protecting the film for forming an insulating layer, as in the conventional film-shaped insulating material of Figure 1 It is made of an insulating layer forming film (2, 20) and mylar films (3, 30) to play the role of the release film, but as shown in Figure 2 cover film 10 is formed in both ends of the insulating layer The height of the film (2, 20) for the jaw, the height of the jaw ({height of the insulation layer forming film) x (width of 1 to 10mm)} having a width of 1 to 10mm is provided in the form provided Alternatively, as shown in FIG. 3, a flow preventing dam 40 having {(height of the insulating layer forming film) × (width of 1 to 10 mm)} is manufactured and located at both ends of the insulating layer forming film layer. It is made in the form of. In this case, the insulating layer forming film 20 is formed to have a width of 10 mm or less, preferably 1 to 10 mm, smaller than the cover film positioned on the upper portion.

The insulating material which can be used in the present invention is easy to handle at room temperature by using a product having a thickness (height) of 70 to 90 µm and a Tg of about 140 ° C., which is softened by heating and heat-resistant and electric by heat curing. It will not specifically limit, if it satisfy | fills the characteristic calculated | required by interlayer insulation materials, such as a characteristic. Particularly, in the present invention, a polyfunctional epoxy, glycidyl acrylate, glycidyl methacrylate, modified bisphenol noble and other diluents are selected from the group consisting of a resin, a photopolymerization initiator and an inorganic filler, which are used in the form of a film.

In addition, the cover film may be a polyolefin such as polyethylene, polyvinyl chloride, polyester such as polyethylene terephthalate, polycarbonate, metal foil (e.g., release paper, copper foil, aluminum foil, etc.), and the like, preferably polyethylene terephthalate. to be. The thickness (height) of the cover film is generally 30 to 40㎛, the cover film may be subjected to a release treatment in addition to the mud treatment, corona treatment. In addition, the cover film has a flow preventing jaw having {(height of the insulating layer forming film) × (width of 1 to 10mm)} at both ends, and when the width of the flow blocking jaw is in the range of 1 to 10mm. The most desirable result can be obtained. In addition, as a release film, the mylar film is laminated on the other side of the insulating material. The mylar film is not particularly limited, and is made of polyethylene, polycarbonate, metal foil, and the like. After lamination to the substrate is removed.

In addition, the flow preventing dam 40 may be made of the same components as the cover film 10, polyolefin such as polyethylene, polyvinyl chloride, polyester such as polyethylene terephthalate, polycarbonate, metal foil (eg, release paper, copper) Foil, aluminum foil, etc.), etc., Preferably it is polyethylene terephthalate. In addition, the flow preventing dam 40 is positioned at both ends of the film layer 20 for forming an insulating layer.

Even when the film-type insulating material is placed on a substrate on which an internal circuit is formed and vacuum-laminated under heating and pressurizing conditions by the flow preventing jaw and the flow preventing dam 40, the insulating material does not flow out from the end of the film. Not only do not contaminate the laminate roll, but also the filling of a large amount of tooling holes (φ 0.8 to 5.0) at the outer side can prevent damage to equipment during post-processing. In addition, the thickness difference of the insulating layer due to excessive flow of the insulating layer around the outer periphery of the substrate does not occur and becomes uniform.

On the other hand, during the horizontal plating process after lamination of the insulation layer, if the clamping position of the plating is concentrated on the resin rather than the copper foil, etching occurs and current distribution worsens, but when the film-type insulating material according to the present invention is used, the insulating material leaks to the outer copper foil. Since the clamp is clamped on the copper foil, the etching phenomenon is prevented and the current distribution is improved, thereby minimizing the plating thickness deviation.

In addition, the insulating material in the form of a film according to the present invention is laminated on a substrate on which an internal circuit is formed by a conventional lamination method.

Hereinafter, the present invention will be described in more detail, but the scope of the present invention is not limited thereto.

Example 1

The film-like insulating material having the form shown in FIG. 2 was arranged on both surfaces of the substrate on a 340 × 510 mm glass epoxy substrate having an internal circuit processed thereon, and the mylar film was removed from the film-like insulating material. A vacuum was applied for 30 seconds to completely remove the air between the insulating material and the substrate and was first pressed in a vacuum at a temperature and pressure of 95 ° C. and 2.7 MPa. After the first press, a second press was carried out at a temperature and a pressure of 90 ° C. and 3 MPa to obtain a printed circuit board on which an insulating material in the form of a film was laminated. At this time, the substrates were stacked without contamination. The resin leaked out and adhered to the substrate was prevented from filling the outer tooling hole or the like.

Example 2

It carried out similarly to Example 1 except having used the film-form insulating material which concerns on FIG. At this time, the substrate and the press were laminated without contamination.

Comparative Example 1

The mylar film was removed from the film-like insulating material after arranging a conventional film-like insulating material as shown in FIG. 1 on both surfaces of the substrate on a 340 × 510 mm glass epoxy substrate having an internal circuit processed thereon. It laminated simultaneously on both surfaces by the press for 30 second at the temperature of 95 degreeC, and the pressure of 2.7 Mpa using the vacuum press machine. At this time, resin leaked from the distal end of the insulation film and adhered to the substrate, and there was no filling in the outer tooling hole.

As can be seen from the above examples and comparative examples, according to the present invention, the insulating material in the form of a film does not leak out from the distal end of the film even when vacuum-laminated under heating and pressurizing conditions, thereby contaminating the press surface or the laminate roll. Instead, the thickness of the insulating layer is uniform, the current distribution is improved during the plating process, the plating thickness is made uniform, and the horizontal copper foil can be protected from the resin so that the plating clamp is correctly connected to the plating during the horizontal plating.

Claims (2)

In the insulating material of the film form consisting of a cover film, an insulating layer forming film and a mylar film, The insulating layer forming film is formed smaller by a width of 1 to 10mm than the cover film located on the upper side, Flow barriers having {(height of the insulating layer forming film) × (width of 1 to 10mm)} are formed at both ends of the cover film to form an insulating layer located below the resin so that the resin of the insulating layer forming film does not flow out. An insulating material in the form of a film, characterized in that it is manufactured to surround the film for use. In the insulating material of the film form consisting of a cover film, an insulating layer forming film and a mylar film, The insulating layer forming film is formed smaller by a width of 1 to 10mm than the cover film located on the upper side, A flow preventing dam having {(height of the insulating layer forming film) × (width of 1 to 10mm)} is manufactured and placed at both ends of the insulating layer forming film layer so that the resin of the insulating layer forming film does not flow out. An insulating material in the form of a film, characterized in that manufactured.