JPH04111496A - High multilayer wiring board - Google Patents

Abstract

PURPOSE:To select through holes at desired positions and sharply improve parts mounting density by using a half through hole, which connects only the wiring layers on one side viewed from the center layer of a substrate, for a through hole, which connects with an inner layer signal layer. CONSTITUTION:A full through hole 3, which pierces stacked wiring boards in thickness direction and make them conductive electrically, is provided, and further two or more half through holes 4, which physically pierce these stacked wiring boards in thickness direction and make approximately half the wiring boards electrically conductive, severally, are provided, and further this is equipped with blind through holes 2. By using the half through holes 4 for the high multilayer wiring board 1, the through holes are communized at the same position, and the through holes, which connects with the inner layer, can be made selective at the desired position, whereby the high density mounting of the parts can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is utilized in the construction of a wiring board. The present invention relates to a high multilayer wiring board having a structure in which through holes (Via) can be shared at the same position.

〔overview〕

In a high multilayer wiring board in which a plurality of wiring boards are connected and stacked by through holes, the present invention connects both sides from the center of the stacked wiring boards using semi-through holes. This allows the holes to be shared, increasing component mounting density.

[Conventional technology]

Conventionally, this type of high-multilayer wiring board has been constructed by connecting two types of through-holes: blind through-holes that relay opposing signal layers and full-through through-holes that pass through all layers, as shown in FIG.

[Problem to be solved by the invention]

The conventional high-multilayer wiring board described above is composed of two types of through holes: blind through holes that connect opposing signal layers and through holes that connect gold layers. All connections to the wiring layers provided on the inner layer were made through through-holes.

In addition, in recent years, high-density mounting has progressed, and the number of double-sided mounting boards is increasing due to the adoption of surface mount components, but through-holes are used for all connections from component pins to inner wiring layers, resulting in through-hole problems. Therefore, there was a drawback that high-density packaging could not be achieved because through-holes could not be provided at desired positions.

The present invention solves these problems, and aims to provide a wiring board in which through holes can be selected at desired positions and component mounting density can be increased.

[Means to solve the problem]

The present invention provides a high multilayer wiring board that includes a laminated wiring board and is provided with a full through hole that penetrates the laminated wiring board in the thickness direction and provides electrical continuity. It is characterized in that a half-through hole is provided that physically penetrates the board in the thickness direction and electrically connects each half of the wiring board.

The semi-penetrating through hole may be two or more, and a blind through hole may be provided.

[Effect]

Lamination is performed using semi-through holes that allow connection of the wiring layers on both sides when viewed from the center layer of the wiring board. This makes it possible to share through-holes at the same location and to select through-holes at desired locations, thereby greatly improving component mounting density.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

The embodiment of the present invention includes a laminated wiring board, and is provided with a full-through hole 3 that penetrates the laminated wiring board in the thickness direction and provides electrical continuity.Furthermore, as a feature of the present invention, Two or more half-through holes 4 are provided that physically penetrate this laminated wiring board in the thickness direction and electrically conduct each half of the wiring board, respectively.Furthermore, a blind through hole 2 is provided. It will be done.

Figure 2 shows a cross section of a conventional high-multilayer wiring board. For example, the component pins 6 mounted on the board and the inner layer signal layer are conventionally connected through all through-holes 3. Therefore, a full through-hole 3 is required for each component pin 6, and high-density packaging is hindered in order to secure the through-hole.

A feature of the present invention is that by using semi-through holes 4 in the high multilayer wiring board 1, the through holes can be shared at the same position, and the through hole to be connected to the inner signal layer can be selected at the desired position. The key point is that high-density mounting of components can be achieved by using this technology.

〔Effect of the invention〕

As explained above, according to the present invention, by using a semi-through hole that connects only the wiring layer on one side when viewed from the center layer of the board to the through hole that connects with the inner signal layer, the through hole connects to the inner signal layer. Hall sharing is now possible,
Through-holes can be selected at desired positions, which has the effect of greatly improving component mounting density.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the configuration of an embodiment of the present invention. FIG. 2 is a sectional view showing the configuration of a conventional example. l... High multilayer wiring board, 2... Blind through hole, 3... Fully penetrating through hole, 4... Half penetrating through hole, 5... Component, 6... Component pin.

Claims (3)

[Claims] 1. In a high-multilayer wiring board that includes a laminated wiring board and is provided with a full through hole that penetrates the laminated wiring board in the thickness direction and provides electrical continuity, the laminated wiring board is physically penetrate the
A high multilayer wiring board characterized by being provided with half-through holes that electrically conduct each half of the wiring board. 2. 2. The high multilayer wiring board according to claim 1, wherein the number of semi-through holes is two or more. 3. The high multilayer wiring board according to claim 1, comprising blind through holes.