SEMI-FINISHED PRODUCT FOR THE PRODUCTION OF CONNECTION SYSTEMS FOR ELECTRONIC COMPONENTS

Abstract

A semi-finished product for the production of connection systems for electronic components including two groups (A, B) of alternately applied conductive layers and insulating layers, wherein first layers (2, 2) of the two groups (A, B) are facing each other to form a separation area for the groups (A, B) to be separated from each other to yield connection systems and the separation area is overlapped and sealed on all sides thereof at least by the two insulating layers (4, 4) following the separation area.

Claims

1. A semi-finished product for the production of connection systems for electronic components, the semi-finished product comprising: two groups (A, B) of alternately applied conductive layers (3) and insulating layers (4, 4) within each of the two groups (A, B), wherein: first layers (2, 2) of each group (A, B) are facing each other to form a separation area where the groups (A, B) are to be separated from each other to yield connection systems for electronic components the first layers (2, 2) being conductive, the conductive layers (3) and insulating layers (4, 4) are applied symmetrically on an outward-facing side of each of the first layers (2, 2), a copper-clad laminate (CCL) core is arranged on an inward-facing side of each of the first layers (2, 2) in the separation area, one or more release layers comprising a material other than copper are arranged between the CCL core and each of the first layers (2, 2), the first layers (2, 2) are held directly against the one or more release layers without directly bonding one first layer (2) to the other first layer (2), and the separation area is overlapped and sealed on all sides thereof by the two insulating layers (4, 4) adjacent to the separation area, alone or in combination with other layers in the separation area.

2. The semi-finished product according to claim 1, wherein the one or more release layers are polymeric.

3. The semi-finished product according to claim 1, wherein the insulating layers (4, 4) are made from prepreg-material.

4. The semi-finished product according to claim 3, wherein the prepreg-material is FR-4-material.

5. The semi-finished product according to claim 1, wherein the insulating layers (4, 4) each have a thickness between 10 m and 80 m.

6. The semi-finished product according to claim 1, wherein at least one of the conductive layers (3) is structured for connection of electronic components.

7. The semi-finished product according to claim 1, wherein the groups (A, B) each are formed by an odd number of conductive layers (3).

Description

[0032] In the following the present invention will be exemplified in more detail by reference to the drawings in which

[0033] FIGS. 1a)-1g) show exemplary steps of the inventive method using the semi-finished product according to the present invention;

[0034] FIG. 2 shows a plan view of one group of conductive and insulating layers wherein an outer layer of the group is overlapped by an insulating layer and

[0035] FIG. 3 shows an exemplary semi-finished product according to the invention; and

[0036] FIG. 4 shows a preferred embodiment of the present invention.

[0037] Obviously, the semi-finished product according to the invention is symmetrical about the separation area arranged between the two groups of alternately applied conductive layers and insulating layers. Wherever possible, the following description will avoid describing both groups of the semi-finished product. It is, however, obvious to the person skilled in the art that this description and the corresponding reference numerals also apply to the other side or the other group of alternately applied conductive layers and insulating layers of the semi-finished product of this invention.

[0038] In FIG. 1a) a group of alternately applied conductive layers and insulating layers is denoted by reference numeral 1. In this particular case, the group 1 consists of outer layers 2 and 3 and an inner layer 4. The outer layers 2 and 3 of the group 1 in this case are conductive layers, for example of copper foil. The inner layer 4 is an insulating layer, for example of prepreg-material, such as FR-4-material. Since the outer layer 2 and outer layer 2 are inward-facing, they are the first layers to be formed. First layer 2 does not stick to the first layer 2 of the second group of alternately applied conductive layers and insulating layers facing it, a separation area is formed between the two groups of alternately applied conductive layers and insulating layers the separation area extending between the first layers 2 and 2 facing each other. As can be seen in FIG. 1a) the separation area is overlapped by the two insulating layers 4 and 4, so that upon lamination, which means application of heat and pressure, the inventive semi-finished product is formed by the resin of the insulating layers 4 and 4 sealing the separation area between the first layers 2 and 2 on all sides thereof as can be seen in FIG. 1b). FIG. 1b) thus shows the inventive semi-finished product. In the step according to FIG. 1c), the semi-finished product according to FIG. 1b) is dressed. Subsequently, holes 5 are drilled, preferably by laser drilling (FIG. 1d)).

[0039] Subsequently, the semi-finished product is subjected to copper plating and via filing (FIG. 1e)) as further exemplary processing steps to provide exemplary electrical functionality to the printed circuit boards to be produced. The step depicted in FIG. 1f) is the step of cutting through the separation area formed by first layers 2 and 2 along the edges thereof, so that the overlap of the insulating layers 4 and 4 surrounding the separation area is removed. Upon removal of this overlap, which overlap is highlighted in FIG. 1e) by the circle 6, the two groups of alternately applied conductive layers 2 and 3 and insulating layers 4 can easily be separated from each other as shown in FIG. 1g). The two printed circuit boards A and B thereby yielded can be further processed to form printed circuit boards of higher complexity. Additional conductive layers and insulating layers can be added by build-up and lamination methods known to the person skilled in the art.

[0040] FIG. 2 shows that the outer layer or the outer conductive layer 2 is smaller in area than the insulating layer 4 following the layer 2, so that the insulating layer 4 will overlap a separation area that is formed by two layers 2 and 2 facing each other as shown in FIG. 1.

[0041] FIG. 3 shows that prior to the cutting step shown in FIG. 1g) additional conductive layers and insulating layers 3 and 4 can be built-up with known methods of printed circuit board-production. In this example all insulating layers overlap the separation area and thus seal the separation area from leakage of chemicals into this area.

[0042] FIG. 4 depicts a preferred variant of the present invention in which a core layer 7 is arranged between the first layers 2 and 2 facing each other. This build-up can be processed to yield the inventive semi-finished product and in particular according to the process steps described in relation to FIG. 1.