CN118829076A - A high frequency circuit board structure and manufacturing method thereof - Google Patents

Abstract

The invention discloses a high-frequency circuit board structure and a manufacturing method thereof, wherein the high-frequency circuit board structure comprises a high-frequency substrate, and the high-frequency circuit board structure comprises: the lower plate surface of the high-frequency substrate is provided with at least one first blind hole, and a first blind hole electroplated layer is formed by electroplating the first blind hole; the upper plate surface of the high-frequency substrate is provided with second blind holes corresponding to the first blind holes, and a second blind hole electroplated layer is formed by electroplating the second blind holes; the second blind hole and the first blind hole are complementary in depth; the second blind hole electroplated layer is contacted with the first blind hole electroplated layer, so that the first blind hole and the second blind hole form conductive connection; the depth of the first blind hole is 20-80% of the thickness of the high-frequency substrate material, the problem of risk of separation reliability of the blind holes is solved, meanwhile, the combined area of the blind holes is increased, and the reliability of blind hole connection is improved.

Description

A high frequency circuit board structure and manufacturing method thereof

Technical Field

The invention relates to a high-frequency circuit board structure and a manufacturing method thereof, belonging to the technical field of circuit boards.

Background Art

At present, high-frequency materials (Roger, etc.) are usually processed using substrates instead of PP materials due to material properties and production requirements. In order to improve the low roughness requirements of copper foil and strengthen the bonding strength between the substrate and the copper foil, special bonding materials are added to the high-frequency material substrate, resulting in the incomplete cleaning of the bottom of the laser hole during the production of HDI blind holes, causing reliability risk problems in blind hole separation. In addition, high-frequency substrate materials require plasma (plasma cleaning machine) to clean the bottom of the laser hole after laser irradiation, and more micro-etching is required to optically inspect the bottom of the laser hole. In addition, when making HDI composite structures, the thickness of the high-frequency substrate is limited by the aspect ratio of the blind hole electroplating, and the copper behind the blind hole electroplating will be too thick, causing antenna accuracy problems when etching the circuit.

Summary of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a high-frequency circuit board structure and a method for manufacturing the same, which solves the above-mentioned blind hole separation reliability risk problem, while increasing the blind hole combination area and improving the reliability of the blind hole connection.

To achieve the above object, the present invention is implemented by adopting the following technical solutions:

In a first aspect, the present invention provides a high-frequency circuit board structure, including a high-frequency substrate, wherein:

The lower surface of the high-frequency substrate has at least one first blind hole, and the first blind hole is electroplated to form a first blind hole electroplating layer;

The upper surface of the high-frequency substrate is provided with a second blind hole at a position corresponding to the first blind hole, and the second blind hole is electroplated to form a second blind hole electroplating layer;

The second blind hole is complementary to the first blind hole in depth;

The second blind hole electroplating layer contacts the first blind hole electroplating layer, so that the first blind hole and the second blind hole form a conductive connection.

Furthermore, the depth of the first blind hole is between 20% and 80% of the thickness of the high-frequency substrate material.

Furthermore, the first blind hole electroplating layer is an electroplating conductive or electroplating filled electroplating layer.

Furthermore, the second blind hole electroplating layer is an electroplating layer filled with electroplating.

Furthermore, a plurality of the first blind holes are distributed on the high-frequency substrate along a linear array.

In a second aspect, the present invention provides a method for manufacturing a high-frequency circuit board structure, comprising:

At least one first blind hole is formed on the lower surface of the high-frequency substrate;

Performing electroplating treatment on the first blind hole to form a first blind hole electroplating layer, and completing the production of the lower board surface circuit layer;

Laminating the high-frequency substrate with electroplating and circuit layer production with the conventional circuit board;

At least one second blind hole is made on the surface of the laminated high-frequency substrate at a position corresponding to the first blind hole, so as to complement the first blind hole in depth;

Performing electroplating on the second blind hole to form a second blind hole electroplating layer, so that the first blind hole and the second blind hole form a conductive connection;

Circuits are fabricated on a high-frequency substrate where the first blind hole and the second blind hole form a conductive connection, thereby forming a high-frequency circuit board.

Furthermore, the depth of the first blind hole is controlled to be 20% to 80% of the thickness of the high-frequency substrate material.

Furthermore, the first blind hole electroplating layer is an electroplating conductive or electroplating filled electroplating layer.

Furthermore, the second blind hole electroplating layer is an electroplating layer filled with electroplating.

Furthermore, a plurality of the first blind holes are distributed on the high-frequency substrate along a linear array.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention provides a high-frequency circuit board structure and a manufacturing method thereof, wherein a single-sided laser blind hole is first manufactured for a high-frequency substrate, and then single-sided electroplating and single-sided circuits are performed, and then conventional processes such as lamination, electroplating, electroplating hole filling, and circuit manufacturing of a composite circuit board are performed. This method solves the above-mentioned blind hole separation reliability risk problem, and at the same time increases the blind hole combination area, thereby improving the reliability of the blind hole connection; in addition, it also solves the problem that after lamination, when making the blind hole, there is no need to make a large hole with a high aspect ratio hole filling electroplating, so that the copper thickness of the antenna area is better controlled, and the circuit accuracy of the antenna area is greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of laser blind vias, electroplating and circuit fabrication on the lower surface of a high-frequency substrate provided by an embodiment of the present invention;

FIG2 is a schematic diagram of high-frequency circuit board lamination provided by an embodiment of the present invention;

3 is a schematic diagram of laser blind vias, electroplating, and electroplating hole filling on a high-frequency substrate provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a high-frequency circuit board circuit manufacturing method according to an embodiment of the present invention.

In the figure: 1. high-frequency substrate; 2. first blind hole; 3. circuit board; 4. second blind hole.

DETAILED DESCRIPTION

The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

Embodiment 1. This embodiment introduces a high-frequency circuit board structure, including: in a composite high-frequency circuit board, at least one first blind hole 2 is provided on the lower surface of a high-frequency substrate 1, and the depth of the blind hole is between 20% and 80% of the material thickness of the high-frequency substrate 1, and a plating layer of the first blind hole 2 is formed; in the composite high-frequency circuit board, a second blind hole 4 is made on the upper surface of the high-frequency substrate 1, corresponding to the center position of the first blind hole 2, and the depth of the blind hole is complementary to the depth of the first blind hole 2, and the bottom of the second blind hole 4 contacts the plating layer at the bottom of the first blind hole 2, and the second blind hole 4 is filled with a plating layer, so that the first blind hole 2 and the second blind hole 4 are conductively connected; the plating layer of the first blind hole 2 can be a plating conductive or plating filled plating layer.

1. The high-frequency circuit board structure of the present invention does not require the original method of plasma cleaning the bottom of the laser hole after laser, nor does it need to be pickled and micro-etched. There is no problem of laser hole bottom inspection recognition rate, and there is no reliability risk problem of blind hole separation caused by incomplete removal of high-frequency materials.

2. The high-frequency circuit board structure of the present invention solves the problem that the material thickness of the high-frequency substrate 1 is relatively thick. When the blind holes are electroplated and filled, only the blind holes of normal size and depth need to be filled, and there is no need to perform a thin copper process, thereby improving the uniformity of the surface copper and the ability to improve the accuracy of the antenna after the circuit is etched.

As shown in FIGS. 1 to 4 , the present embodiment further provides a method for manufacturing a high-frequency circuit board structure according to the above-mentioned method, comprising: (1) a high-frequency substrate 1; (2) forming at least one first blind hole 2 on the lower surface of the high-frequency substrate 1, wherein the depth of the blind hole is between 20% and 80% of the material thickness of the high-frequency substrate 1; (3) forming a first blind hole 2 electroplating layer and a lower surface circuit layer on the lower surface of the high-frequency substrate 1; (4) pressing the high-frequency substrate 1 formed in step (3) and a conventional circuit board 3 to form a composite mixed-pressed high-frequency circuit board; (5) forming a second blind hole 4 on the upper surface of the high-frequency substrate 1, corresponding to the center position of the first blind hole 2, wherein the depth of the blind hole is complementary to that of the first blind hole 2, wherein the bottom of the second blind hole 4 contacts the electroplating layer at the bottom of the first blind hole 2, and forming an electroplating layer that fills the second blind hole 4 with electroplating, so that the first blind hole 2 and the second blind hole 4 are electrically connected; and (6) performing circuit manufacturing, i.e., forming a high-frequency multi-layer mixed-pressed circuit board of the present invention.

The high-frequency substrate 1 structure formed by the manufacturing method of this embodiment can avoid the reliability problem of blind hole connection and improve the line accuracy of the antenna, while solving the process and inspection problems of the original method.

Embodiment 2: This embodiment provides a method for manufacturing a high-frequency circuit board structure, comprising:

At least one first blind hole 2 is formed on the lower surface of the high-frequency substrate 1;

Performing electroplating treatment on the first blind hole 2 to form an electroplating layer of the first blind hole 2, and completing the production of the lower board surface circuit layer;

Laminating the high-frequency substrate 1 after electroplating and circuit layer production with the conventional circuit board 3;

At least one second blind hole 4 is made at a position corresponding to the first blind hole 2 on the surface of the laminated high-frequency substrate 1, which is complementary to the first blind hole 2 in depth; the depth of the first blind hole 2 is controlled to be 20% to 80% of the thickness of the high-frequency substrate 1 material.

Performing electroplating treatment on the second blind hole 4 to form an electroplating layer of the second blind hole 4, so that the first blind hole 2 and the second blind hole 4 form a conductive connection;

Circuits are fabricated on the high-frequency substrate 1 where the first blind via 2 and the second blind via 4 form a conductive connection, thereby forming a high-frequency circuit board.

The electroplating layer of the first blind hole 2 is an electroplating conductive or electroplating filled electroplating layer, and the electroplating layer of the second blind hole 4 is an electroplating filled electroplating layer.

The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims (10)

1. A high-frequency circuit board structure, characterized in that it includes a high-frequency substrate, wherein: The lower surface of the high-frequency substrate has at least one first blind hole, and the first blind hole is electroplated to form a first blind hole electroplating layer; The upper surface of the high-frequency substrate is provided with a second blind hole at a position corresponding to the first blind hole, and the second blind hole is electroplated to form a second blind hole electroplating layer; The second blind hole is complementary to the first blind hole in depth; The second blind hole electroplating layer contacts the first blind hole electroplating layer, so that the first blind hole and the second blind hole form a conductive connection. 2. The high-frequency circuit board structure according to claim 1 is characterized in that the depth of the first blind hole is between 20% and 80% of the thickness of the high-frequency substrate material. 3. The high-frequency circuit board structure according to claim 1 is characterized in that the first blind hole electroplating layer is an electroplating conductive or electroplating filled electroplating layer. 4. The high-frequency circuit board structure according to claim 1, characterized in that the second blind hole electroplating layer is an electroplating layer filled with electroplating. 5 . The high-frequency circuit board structure according to claim 1 , wherein a plurality of the first blind holes are distributed on the high-frequency substrate along a linear array. 6. A method for manufacturing a high-frequency circuit board structure, characterized by comprising: At least one first blind hole is formed on the lower surface of the high-frequency substrate; Performing electroplating treatment on the first blind hole to form a first blind hole electroplating layer, and completing the production of the lower board surface circuit layer; Laminating the high-frequency substrate with electroplating and circuit layer production with the conventional circuit board; At least one second blind hole is made on the surface of the laminated high-frequency substrate at a position corresponding to the first blind hole, so as to complement the first blind hole in depth; Performing electroplating on the second blind hole to form a second blind hole electroplating layer, so that the first blind hole and the second blind hole form a conductive connection; Circuits are fabricated on a high-frequency substrate where the first blind hole and the second blind hole form a conductive connection, thereby forming a high-frequency circuit board. 7. The method for manufacturing a high-frequency circuit board structure according to claim 6, wherein the depth of the first blind hole is controlled to be 20% to 80% of the thickness of the high-frequency substrate material. 8 . The method for manufacturing a high-frequency circuit board structure according to claim 6 , wherein the first blind hole electroplating layer is an electroplating conductive layer or an electroplating filled layer. 9 . The method for manufacturing a high-frequency circuit board structure according to claim 6 , wherein the second blind hole electroplating layer is an electroplating layer filled with electroplating. 10 . The method for manufacturing a high-frequency circuit board structure according to claim 6 , wherein a plurality of the first blind holes are distributed on the high-frequency substrate along a linear array.