JP2016207850A - Manufacturing method for printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict peeling between a resin insulation layer, and a conductor layer and veer hole conductor.SOLUTION: A manufacturing method for a printed board comprises: the step of preparing an intermediate substrate having a lower-layer resin insulation layer and a lower-layer conductor layer on the lower-layer resin insulation layer; the step of forming an upper-layer resin insulation layer in a semi-cured state from semi-cured resin film by stacking the semi-cured resin film with a support film onto the intermediate substrate such that the lower-layer conductor layer and the semi-cured resin film are stacked opposite each other; the step of forming a veer hole on the upper-layer resin insulation layer in the semi-cured state via the support film; the step of roughing an exposed surface of the upper-layer resin insulation layer in the semi-cured state and the wall surface of the veer hole after removal of the support film; the step of completely curing the upper-layer resin insulation layer in the semi-cured state; and the step of forming in the veer hole a veer hole conductor conducting with the lower-layer conductor layer and also forming an upper-layer conductor layer on the upper-layer resin insulation layer in the completely cured state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a printed wiring board.

  Patent document 1 is disclosing the manufacturing method of a printed wiring board. And according to the manufacturing process of the wiring board which concerns on 1st Embodiment of patent document 1, first, the semi-hardened resin insulating layer supported by the support film is laminated | stacked on a core board | substrate. Thereafter, the semi-cured resin insulation layer is cured. And a via hole is formed in the resin insulation layer by irradiating the cured resin insulation layer with a laser through a support film. Next, the support film is removed, and the surface of the resin insulating layer and the wall surface of the via hole are roughened. Thereafter, a conductor layer and a via hole conductor are formed on the roughened resin insulating layer and in the via hole by a semi-additive method, and a printed wiring board is manufactured.

JP 2009-099649 A

  The manufacturing method disclosed in Patent Document 1 includes a step in which the resin insulating layer is cured before the resin insulating layer is roughened. For this reason, selective etching of the resin insulating layer becomes difficult, and even if the roughening time is increased, the roughness of the unevenness of the surface of the resin insulating layer and the wall surface of the via hole does not increase. Therefore, in the manufacturing method disclosed in Patent Document 1, the surface of the resin insulating layer and the wall surface of the via hole cannot be sufficiently roughened, the adhesion strength between the resin insulating layer, the conductor layer, and the via hole conductor is lowered, and the heat Peeling between the insulating layer, the conductor layer, and the via-hole conductor occurred due to a cycle or the like.

  The object of the present invention is to sufficiently roughen the surface of the resin insulation layer and the wall surface of the via hole, achieve high adhesion strength between the resin insulation layer, the conductor layer and the via hole conductor, and form the resin insulation layer, the conductor layer and the via hole. It is providing the manufacturing method of the printed wiring board by which peeling between conductors is suppressed.

  A first aspect of the method for producing a printed wiring board according to the present invention is a method for producing a printed wiring board comprising a resin insulating layer and a conductor layer alternately: on the lower resin insulating layer and the lower resin insulating layer. An intermediate substrate having a lower conductive layer is prepared; and a semi-cured resin film with a support film is laminated on the intermediate substrate in a direction in which the lower conductive layer and the semi-cured resin film face each other. A step of forming a semi-cured upper resin insulating layer with the semi-cured resin film; a step of forming a via hole in the semi-cured upper resin insulating layer through the support film; After the support film is removed, the exposed surface of the upper resin insulating layer in the semi-cured state and the via hole wall surface are roughened; the upper resin insulating layer in the semi-cured state is fully cured; Forming a via hole conductor in conduction with the lower conductor layer in the via hole, and forming an upper conductor layer on the via hole conductor and the upper resin insulating layer in the fully cured state. Yes.

  A second aspect of the method for producing a printed wiring board according to the present invention is a method for producing a printed wiring board comprising alternately a resin insulating layer and a conductor layer: on the lower resin insulating layer and on the lower resin insulating layer An intermediate substrate having a lower conductive layer is prepared; and a semi-cured resin film with a support film is laminated on the intermediate substrate in a direction in which the lower conductive layer and the semi-cured resin film face each other. A step of forming a semi-cured upper resin insulating layer with the semi-cured resin film; a step of forming a via hole in the semi-cured upper resin insulating layer through the support film; A step of roughening the exposed surface of the semi-cured upper resin insulation layer and the wall surface of the via hole after removing the support film; and a via hole that is electrically connected to the lower conductor layer in the via hole. A step of forming an upper conductor layer on the via-hole conductor and the semi-cured upper resin insulating layer; and a step of fully curing the semi-cured upper resin insulating layer. And have;

(A)-(g) is a figure which shows one Embodiment of the manufacturing method of the printed wiring board of this invention in order of a process. (A)-(g) is a figure which shows other one Embodiment of the manufacturing method of the printed wiring board of this invention to process order.

  Hereinafter, embodiments of a printed wiring board of the present invention will be described with reference to the drawings. FIGS. 1A to 1G are diagrams showing an embodiment corresponding to the first aspect of the method for producing a printed wiring board of the present invention in the order of steps.

  In the printed wiring board manufacturing method of the present embodiment, first, as shown in FIG. 1A, a lower resin insulating layer 1 and a lower conductor layer 2 formed on the lower resin insulating layer 1 are provided. An intermediate substrate preparation step in which the intermediate substrate 3 is prepared is performed. Here, as the lower resin insulating layer 1, for example, a layer formed by curing an epoxy resin impregnated in a core material such as glass cloth can be used.

  Next, as shown in FIG. 1B, a semi-cured resin film 5 with a support film 4 is laminated on the intermediate substrate 3 so that the lower conductor layer 2 and the semi-cured resin film 5 face each other. Then, a resin film laminating step is performed in which the semi-cured resin film 5 forms an upper resin insulating layer (indicated by the same reference numeral as the semi-cured resin film) 5 in a semi-cured state. For joining the intermediate substrate 3 and the semi-cured resin film 5 at the time of lamination, for example, a method such as a heating and pressing press can be used. As the support film 4, for example, a film such as PET (polyethylene terephthalate) can be used. As the semi-cured resin film 5, for example, an epoxy resin film having thermosetting properties can be used. By this resin film laminating step, the laminate shown in FIG. 1C can be obtained.

  Next, as shown in FIG. 1 (d), a via hole forming step is performed in which a via hole 6 is formed in the upper resin insulating layer 5 in a semi-cured state via the support film 4. The via hole 6 can be formed by irradiating a portion where the via hole 6 is to be formed with laser light to melt the support film 4 and the semi-cured upper resin insulating layer 5 together. The semi-cured upper resin insulating layer 5 defines a via hole 6 by a via hole wall surface 5a.

  Next, as shown in FIG. 1 (e), after the support film 4 is removed, for example, by peeling off the semi-cured upper resin insulation layer 5, the semi-cured upper resin insulation layer 5 is removed. A roughening step is performed in which the surface 5b and the via-hole wall surface 5a are roughened. For example, an epoxy resin having a different molecular weight is blended and used in the semi-cured resin film 5 to form a resin layer having a composite phase structure by phase separation, and the upper-layer resin in a semi-cured state after removal of the support film 4 The resin of a specific phase is removed from the insulating layer 5 with a specific chemical, or an inorganic fine powder such as silica or calcium carbonate is dispersed in the resin matrix of the semi-cured resin film 5, and the support film 4 is removed. The surface of the upper resin insulation layer 5 in the semi-cured state is utilized by using known selective etching such that the inorganic fine powder is selectively eluted with a specific chemical from the upper resin insulation layer 5 in the semi-cured state. 5b and via hole wall surface 5a are roughened. (For example, refer to Japanese Patent Laid-Open No. 7-154069).

  Next, as shown in FIG. 1 (f), a main curing step is performed in which the upper resin insulating layer 5 in a semi-cured state is finally cured. When the upper resin insulating layer 5 is made of, for example, a thermosetting resin film, the main curing of the upper resin insulating layer 5 in the semi-cured state is performed at the curing temperature of the upper resin insulating layer 5 in the semi-cured state. Can be performed by heating at a high temperature for a predetermined time. If the upper resin insulating layer 5 is made of, for example, a photocurable resin film, the upper resin insulating layer 5 in the semi-cured state is exposed to light of a predetermined wavelength such as ultraviolet rays for a predetermined time. it can.

  Finally, as shown in FIG. 1 (g), a via-hole conductor 7 is formed in the via-hole 6 to be electrically connected to the lower-layer conductor layer 2, and the upper-layer resin insulation layer on the via-hole conductor 7 and after the main curing. A conductor layer forming step is performed in which an upper conductor layer 8 including a wiring pattern is formed on 5. For example, a semi-additive method can be used to form the via-hole conductor 7 and the upper conductor layer 8.

  According to the embodiment shown in FIGS. 1A to 1G described above, the upper resin insulating layer 5 is in a semi-cured state before the roughening step, and thus can be selectively etched in the roughening step. By increasing the roughening time (etching time), the roughness of the unevenness of the surface 5b of the upper resin insulating layer 5 and the via hole wall surface 5a can be increased. Therefore, the surface 5b of the upper resin insulation layer 5 and the via hole wall surface 5a can be sufficiently roughened, and high adhesion strength between the upper resin insulation layer 5, the via hole conductor 7, and the upper conductor layer 8 can be achieved. Peeling between the upper resin insulating layer 5 and the via-hole conductor 7 and the upper conductor layer 8 is suppressed.

  FIGS. 2A to 2G are views showing another embodiment corresponding to the second aspect of the printed wiring board manufacturing method of the present invention in the order of steps. In each step of FIGS. 2 (a) to 2 (g), a portion formed by the same method as the portion formed in the steps shown in FIGS. 1 (a) to (g) is assigned the same reference numeral. Explanation is omitted.

  In the embodiment shown in FIGS. 2A to 2G, the difference from the embodiment shown in FIGS. 1A to 1G is the order of the main curing step. That is, in the embodiment shown in FIGS. 1A to 1G, as shown in FIG. 1F, the main curing process is performed between the roughening process and the conductor layer forming process. On the other hand, in the embodiment shown in FIGS. 2A to 2G, the main curing step is performed after the conductor layer forming step as shown in FIG. 2G. Also in the embodiment shown in FIGS. 2A to 2G, the upper resin insulation layer 5 is in a semi-cured state before the roughening step, and therefore the example shown in FIGS. 1A to 1G. Similarly to the above, the roughness of the unevenness of the surface 5b of the upper resin insulation layer 5 and the via hole wall surface 5a can be increased by the roughening step.

  As a suitable example of the method for producing a printed wiring board of the present invention, both the embodiment shown in FIGS. 1 (a) to (g) and the embodiment shown in FIGS. 2 (a) to (g) are shown in FIG. Between the resin film laminating step shown in FIG. 2C and FIG. 2C and the via hole forming step shown in FIG. 1D and FIG. However, for example, a temporary curing step can be added in which it is temporarily cured to such an extent that it is lightly pressed with a finger and does not dent. If the semi-cured upper resin insulation layer 5 is temporarily cured before the via hole forming step, deformation during transportation of the printed wiring board during manufacture is prevented, and handling becomes easy.

  If the upper resin insulation layer 5 is made of, for example, a thermosetting resin film, the semi-cured upper resin insulation layer 5 is temporarily cured from the curing temperature of the upper resin insulation layer 5 in the semi-cured state. The heating can be performed at a higher temperature for a shorter time than in the case of the main curing, or by heating at a temperature lower than the curing temperature. If the upper resin insulation layer 5 is made of, for example, a photocurable resin film, the semi-cured upper resin insulation layer 5 is exposed to light of a predetermined wavelength such as ultraviolet rays for a shorter time than in the case of main curing. Can be performed.

  In the method for producing a printed wiring board of the present invention, both the embodiment shown in FIGS. 1A to 1G and the embodiment shown in FIGS. ) To (g) or similar to the steps shown in FIGS. 2B to 2G, the upper resin insulation layer 5 and the upper conductor are further formed on the upper resin insulation layer 5 and the upper conductor layer 8. A multilayer printed wiring board may be manufactured by alternately laminating the layers 8 one by one or a plurality of layers.

DESCRIPTION OF SYMBOLS 1 Lower resin insulation layer 2 Lower conductive layer 3 Intermediate substrate 4 Support film 5 Upper resin insulation layer (semi-cured resin film)
5a Via hole wall surface 5b Surface 6 Via hole 7 Via hole conductor 8 Upper conductor layer

Claims (3)

A method for manufacturing a printed wiring board comprising alternating resin insulation layers and conductor layers, comprising:
A step of preparing an intermediate substrate having a lower resin insulation layer and a lower conductor layer on the lower resin insulation layer;
A semi-cured resin film with a support film is laminated on the intermediate substrate so that the lower conductor layer and the semi-cured resin film face each other, and the semi-cured resin upper layer is semi-cured by the semi-cured resin film. A step of forming
A step of forming a via hole in the semi-cured upper resin insulating layer through the support film;
A step of roughening the exposed surface of the semi-cured upper resin insulation layer and the wall surface of the via hole after removing the support film;
A step in which the upper resin insulating layer in the semi-cured state is fully cured;
A step of forming a via-hole conductor in conduction with the lower-layer conductor layer in the via-hole, and forming an upper conductor layer on the via-hole conductor and the upper resin insulating layer in the fully cured state;
It has. A method for manufacturing a printed wiring board comprising alternating resin insulation layers and conductor layers, comprising:
A step of preparing an intermediate substrate having a lower resin insulation layer and a lower conductor layer on the lower resin insulation layer;
A semi-cured resin film with a support film is laminated on the intermediate substrate so that the lower conductor layer and the semi-cured resin film face each other, and the semi-cured resin upper layer is semi-cured by the semi-cured resin film. A step of forming
A step of forming a via hole in the semi-cured upper resin insulating layer through the support film;
A step of roughening the exposed surface of the semi-cured upper resin insulation layer and the wall surface of the via hole after removing the support film;
Forming a via-hole conductor in conduction with the lower-layer conductor layer in the via-hole, and forming an upper conductor layer on the via-hole conductor and the semi-cured upper resin insulating layer;
A step in which the upper resin insulating layer in the semi-cured state is fully cured;
It has.   It is a manufacturing method of the printed wiring board of Claim 1 or 2, Comprising: The said semi-hardened state between the process in which the upper resin insulation layer of the said semi-hardened state is formed, and the process in which the said via hole is formed. And a step of temporarily curing the upper resin insulation layer.

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