WO2022006981A1

WO2022006981A1 - Inner-layer board structure for lcp substrate and lcp substrate

Info

Publication number: WO2022006981A1
Application number: PCT/CN2020/102722
Authority: WO
Inventors: 陈康; 陈勇利; 韩佳明; 阮桂祥
Original assignee: 瑞声声学科技(深圳)有限公司; 瑞声科技(新加坡)有限公司
Priority date: 2020-07-08
Filing date: 2020-07-17
Publication date: 2022-01-13
Also published as: CN212936279U

Abstract

Disclosed in the present application are an inner-layer board structure for an LCP substrate and the LCP substrate. The inner-layer board structure comprises a base body, wherein the base body is provided with a conductive layer, and the conductive layer is provided with an inner-layer circuit. The base body is exposed out, after at least part of the conductive layer being etched, thereby forming a positioning part capable of being exposed out of the base body on the conductive layer; and the conductive layer at the periphery of the positioning part is connected to the inner-layer circuit. When the inner-layer board structure in the present application is subjected to high-temperature pressing, the deviation trends of the positioning part and the inner-layer circuit are the same, so that the problem that the alignment precision between the inner-layer board structure and an outer-layer board structure is affected due to the dislocation between the positioning part and the inner-layer circuit can be solved, and the performance of the LCP substrate can be improved.

Description

Inner layer board structure for LCP substrate and LCP substrate

technical field

The present application relates to the technical field of circuit boards, and in particular, to an inner layer board for an LCP substrate and an LCP substrate.

Background technique

With the rapid development of 5G communication technology and millimeter wave technology, the demand for high-frequency high-speed FPC (flexible circuit board) has risen sharply.

technical problem

As a kind of high frequency and high speed FPC, LCP substrate is widely used in the industry. The LCP substrate is a multi-layer board, and the connection between the boards is mostly realized by high-temperature lamination without glue. The inner layer board of the existing LCP substrate is usually etched with copper pads that are separated from the inner layer circuit, and at the same time, a window treatment is performed at the corresponding position of the outer layer board, so that the copper pads can be exposed from the outer layer board. Thereby, the positioning of the inner layer board and the outer layer board is realized. In the process of high temperature lamination without glue, the inner layer will melt due to the influence of high temperature, causing the inner layer circuit to be offset. The independent setting of the copper pad and the inner layer circuit will cause the degree of offset between the two. This will cause dislocation between the copper pads and the inner layer circuit, which will affect the alignment accuracy of the inner layer board and the outer layer board, resulting in deviations in the positioning of the LCP substrate after lamination, and finally The performance of the LCP substrate is affected.

technical solutions

The present application discloses an inner-layer board structure for an LCP substrate and the LCP substrate, which are used to solve the problem of easy dislocation between the copper pads and the inner-layer circuit of the existing inner-layer board during the high-temperature lamination process .

To this end, according to the first aspect, an embodiment provides an inner layer board structure for an LCP substrate, including:

a base, with a conductive layer on the base, and an inner layer circuit formed on the conductive layer;

Wherein, at least part of the conductive layer is etched to expose the substrate, so that a positioning portion capable of exposing the substrate is formed on the conductive layer, and the conductive layer on the periphery of the positioning portion is connected to the inner layer circuit.

In some embodiments of the inner layer panel structure, the cross-section of the positioning portion is circular.

In some embodiments of the inner layer panel structure, the positioning portion is located at an edge of the base body.

In some embodiments of the inner-layer board structure, a marking indication portion is further etched on the conductive layer for marking the positioning portion, so as to facilitate the identification of the positioning portion.

In some embodiments of the inner layer board structure, the marking indication portion is arranged around the positioning portion, and the marking indication portion has a structure adapted to the positioning portion.

According to a second aspect, an embodiment provides an LCP substrate including the inner layer board structure according to the first aspect of the present application.

In some embodiments of the LCP substrate, an outer layer plate structure is further included, and the outer layer plate structure has a structure adapted to the inner layer plate structure.

In some embodiments of the LCP substrate, the inner-layer board structure and the outer-layer board structure are both rectangular, and the positioning parts in the inner-layer board structure are arranged at four corners of the rectangle.

In some embodiments of the LCP substrate, the outer layer board structure is provided with a window, and the window is disposed opposite to the positioning portion, so that the positioning portion can be exposed from the window.

In some embodiments of the LCP substrate, the width of the LCP substrate is 250 mm, the length is 250 mm˜500 mm, and the distance between the edge of the window and the edge of the LCP substrate is greater than 10 mm.

beneficial effect

The beneficial effect of the present application is that: since the positioning part is directly formed by the conductive layer, and the positioning part is connected with the inner layer circuit, the deviation tendency of the positioning part and the inner layer circuit is converged when the inner layer board structure is pressed at a high temperature , so that the problem of affecting the alignment accuracy between the inner-layer board structure and the outer-layer board structure caused by the dislocation between the two can be improved, and the performance of the LCP substrate can be improved.

Description of drawings

FIG. 1 shows a schematic structural diagram of an inner layer board structure provided according to an embodiment of the present application;

FIG. 2 shows a schematic structural diagram of an outer layer plate structure provided according to an embodiment of the present application;

FIG. 3 shows a schematic structural diagram of an LCP substrate provided in an embodiment of the present application in a high-temperature lamination process;

FIG. 4 shows another schematic structural diagram of an LCP substrate provided in an embodiment of the present application during a high-temperature lamination process

Description of main component symbols:

100-inner layer board structure; 200-outer layer board structure; 110-base body; 120-conductive layer; 130-positioning part; 140-mark indication part; 210-window.

Embodiments of the present invention

To further illustrate each practical example, the present application provides accompanying drawings. These drawings are part of the disclosure content of the present application, and are mainly used to illustrate the embodiments, and can be used in conjunction with the relevant description of the specification to explain the operation principles of the embodiments. With reference to these contents, one of ordinary skill in the art will understand other possible implementations and advantages of the present application. Components in the figures are not drawn to scale, and similar component symbols are often used to represent similar components.

The present application will be further described below with reference to the accompanying drawings and embodiments.

The embodiments of the present application provide an LCP substrate. The LCP substrate is improved in structure so that the alignment accuracy between multilayer boards can be improved during high temperature lamination, thereby improving the performance of the LCP substrate.

It should be noted that the number of layers of the LCP substrate can be determined according to requirements. For the convenience of description and understanding, the following embodiments will be described by taking the double-layer plate structure as an example, but it should be understood that the related The technical means can be applied to LCP substrates with more layer structures without any obstacles.

In one embodiment, please refer to FIG. 1 , the inner layer board structure 100 includes a base 110 , a conductive layer 120 is formed on the base 110 , the base 110 is formed of liquid crystal polymer, and the conductive layer 120 is made of conductive material formed, the conductive layer 120 is formed with inner layer lines for conducting electricity. Part of the conductive layer 120 is etched to expose the base body 110 , so that a positioning portion 130 capable of exposing the base body 110 is formed on the conductive layer 120 , and the positioning portion 130 is connected to the inner layer circuit.

Generally speaking, the inner layer circuit on the base body 110 is formed of copper foil, so in actual design, the positioning portion 130 can be formed on the copper foil on the base body 110 .

In the embodiment of the present application, it can be understood that when the inner-layer board structure 100 participates in high-temperature lamination, since the positioning portion 130 is directly formed of the conductive layer 120 and the positioning portion 130 is connected to the inner-layer circuit, the base 110 During the melting process, the positioning portion 130 and the inner layer circuit can be displaced in the same trend, and there will be no dislocation between the two, so that the impact of the dislocation between the inner layer board structure 100 and the outer layer can be improved. The problem of alignment accuracy between the plate structures 200 can improve the performance of the LCP substrate.

In a specific embodiment, the cross-section of the positioning portion 130 is circular, so that the structure of the positioning portion 130 itself will not change too much during the high-temperature pressing process, so that the high-temperature pressing process can always be guaranteed. positioning accuracy.

In other embodiments, the positioning portion 130 may also adopt other structural forms, for example, its cross section may also be a square or a triangle.

In a specific embodiment, the positioning portion 130 is disposed at the edge of the base body 110 , so that more space can be reserved for the inner layer circuit, and the structure of the positioning portion 130 itself can be prevented from being changed to a great extent.

It should be noted that the specific position of the positioning portion 130 relative to the base body 110 can be changed in various ways. Generally speaking, the distance between the positioning portion 130 and the edge of the base body 110 should not be less than 10 mm.

On the other hand, for the LCP substrate as a whole, in addition to the positioning portion 130 , other pads or positioning points are generally provided on the base 110 , which may cause confusion and misidentification of the positioning portion 130 .

In this regard, in a specific embodiment, a marking indication part 140 is further etched on the base body 110 for marking the positioning part 130 so as to facilitate the identification of the positioning part 130 .

It can be understood that the marking indication part 140 and the positioning part 130 are in a matching relationship, and the area occupied by the two and the overall structure formed by the two can be sufficiently distinguished from other pads or positioning points, so it can facilitate the identification of the positioning part 130. effect.

It should be noted that the marking indication portion 140 should be set close to the positioning portion 130. For example, the marking indication portion 140 may surround the outer circumference of the positioning portion 130. During the high temperature pressing process, the two can be offset synchronously. The formed external representations (such as the area occupied by the two, the overall structure formed by the two, etc., described above) undergo regular changes that can be captured or identified, and always retain the functions that are easy to identify.

As for the specific structure of the mark indicating part 130, it can take various forms. For example, it can be designed following the positioning portion 130. For example, when the positioning portion 130 adopts the positioning portion 130 with a circular cross-section in the previous embodiment, the marking indication portion 140 can also be configured with a circular cross-section, and in order to improve the For identification performance, there can be a plurality of marking indicating parts so that they can surround the outer circumference of the positioning part 130. Of course, the marking indicating part 140 can also be configured to have an arc-shaped section, or even a roughly triangular section (as shown in FIG. 1 ). ), the purpose of surrounding the positioning portion 130 can also be achieved.

It can be seen from the foregoing that when the positioning portion 130 adopts a circular cross-section and the marking indicating portion 140 adopts the above structure, the structural changes of the positioning portion 130 and the marking indicating portion 140 during the high temperature pressing process can be minimized.

Of course, the marking indicating part 140 may also adopt other various structural forms, and the marking indicating part 140 and the positioning part 130 may have various structural combinations, which will not be described in detail herein.

In an embodiment, please refer to FIG. 2 , the outer layer board structure 200 has a structure adapted to the inner layer board structure 100 .

It should be noted here that "fit" refers to the fact that the outer-layer board structure 200 and the inner-layer board structure 100 can always fit together during the high-temperature lamination process, and the edge shapes can overlap, for example, when When the inner layer panel structure 100 is a rectangular structure (as shown in FIG. 1 ), the outer layer panel structure 200 should also be a rectangular structure (as shown in FIG. 2 ).

Of course, the inner-layer board structure 100 and the outer-layer board structure 200 do not necessarily have to be structurally matched, and various deformations can be made in the structure. For example, in some cases, the area of the outer layer panel structure 200 may be larger than that of the inner layer panel structure 100, and the outer layer panel structure 200 may adopt a different structural form than the inner layer panel structure 100, for example, when the inner layer panel structure When 100 is a rectangle, the outer layer panel structure 200 may be a circular structure.

For ease of understanding, an example in which the inner layer board structure 100 and the outer layer board structure 200 are both rectangular is described herein. At this time, the LCP substrate has a rectangular structure as a whole.

Referring to FIG. 1 , the positioning portions 130 in the inner layer board structure 100 are disposed at the four corners of the rectangle, which is convenient for etching the positioning portions 130 and can also leave more space for the inner layer circuit.

For the outer layer panel structure 200 , please refer to FIG. 2 , the four corners can be opened with a window, so that each of the four corners is formed with a window 210 , and the window 210 needs to be opposite to the positioning portion 130 . It is arranged so that the positioning portion 130 can be exposed from the opening 210, and the alignment accuracy between the inner layer board structure 100 and the outer layer board structure 200 is ensured during the high temperature pressing process.

It can be understood that the opening 210 can be adapted to the structure of the positioning portion 130 , for example, when the cross-section of the positioning portion 130 is circular, the opening 210 can be designed as a circular hole. In addition, the inner diameter of the opening should be larger than the outer diameter of the positioning portion 130 .

In some specific embodiments, the radius of the positioning portion 130 is 0.2 mm˜1.0 mm, and the radius of the opening 210 may be 1.5 mm˜3.2 mm. In the embodiment provided with the marking indicating portion 130, when the marking indicating portion 130 adopts an arc-shaped structure, the arc radius of the marking indicating portion 130 may be 1.2 mm˜2.2 mm.

In some specific embodiments, the width of the LCP substrate is 250mm, the length is 250mm˜500mm, and the distance between the edge of the window 210 and the edge of the LCP substrate is greater than 10mm, while ensuring the positioning stability, the LCP substrate can be of internal wiring to leave more room.

In the embodiment of the present application, due to the improvement of the structure of the inner layer board structure 100, the alignment accuracy of the outer layer board structure 200 and the inner layer board structure 100 is high during the high temperature compression molding process of the LCP substrate, which is beneficial to To improve the performance of the LCP substrate, the production process of the LCP substrate will be described below with reference to Figures 1-4, and the above effects will be re-explained.

First, referring to FIG. 1 , a base body 110 with a predetermined shape (for example, a rectangle) is made of a corresponding material, and the conductive layer 120 on the surface of the base body 100 is processed (eg, etching treatment) to form an inner layer circuit on the conductive layer. Then, a positioning portion 130 is formed on the substrate by etching, and the conductive layer portion of the positioning portion 130 is connected to the inner layer circuit to form the inner layer board structure 100 .

Next, referring to FIG. 2 , a corresponding material is used to make an outer layer board structure 200 that is structurally compatible with the inner layer board structure 100 , and at the same time, the outer layer board structure 200 is located at a position corresponding to the positioning portion 130 . Perform window opening process to form window opening 210;

Next, referring to FIG. 3 , the outer layer board structure 200 is attached to the inner layer board structure 100 , so that the positioning portion 130 is exposed from the opening 210 ;

Finally, referring to FIG. 4 , the inner-layer board structure 100 and the outer-layer board structure 200 are subjected to high-temperature lamination. During the high-temperature lamination process, the positioning portion 130 on the inner-layer board structure 100 and the inner-layer circuit follow the same trend. Offset, there will be no positional deviation between the two, and the two will not be misaligned, and then the offset lines of the two are under control. After the lamination is completed, accurate process positioning can be performed, thereby improving the LCP substrate. performance.

It should be noted that the LCP substrate in this application includes the inner layer plate structure 100 and the outer layer plate structure 200. The meanings of "inner" and "outer" here are defined based on the manufacturing process of the LCP substrate. During the high-temperature lamination process, the outer layer board structure 200 needs to be placed outside the inner layer board structure 100 so that the positioning portion 130 can be seen through the opening window 210, so the outer layer board structure 200 at the near end of the line of sight is on the outside. On the inside is the inner layer panel structure 100 at the far end of the line of sight.

In other scenarios, the positional relationship between the inner layer panel structure 100 and the outer layer panel structure 200 should be flexibly understood.

The above are only the embodiments of the present application. It should be pointed out that for those of ordinary skill in the art, improvements can be made without departing from the creative concept of the present application, but these belong to the present application. scope of protection.

Claims

The inner layer board structure for LCP substrate is characterized in that, it includes:

a base, with a conductive layer on the base, and an inner layer circuit formed on the conductive layer;

Wherein, at least part of the conductive layer is etched to expose the substrate, so that a positioning portion capable of exposing the substrate is formed on the conductive layer, and the conductive layer on the periphery of the positioning portion is connected to the inner layer circuit.
The inner-layer board structure for an LCP substrate according to claim 1, wherein the cross-section of the positioning portion is circular.
The inner layer board structure for an LCP substrate according to claim 1, wherein the positioning portion is located at the edge of the base body.
The inner layer board structure for an LCP substrate according to any one of claims 1 to 3, wherein a marking indication portion is etched on the conductive layer for marking the positioning portion, so as to facilitate the Identify the positioning portion.
The inner layer board structure for an LCP substrate according to claim 4, wherein the marking indication portion is arranged around the positioning portion, and the marking indication portion has a structure adapted to the positioning portion .
The LCP substrate is characterized by comprising the inner layer board structure according to any one of claims 1-5.
The LCP substrate of claim 6, further comprising an outer layer board structure, the outer layer board structure having a structure adapted to the inner layer board structure.
The LCP substrate of claim 7, wherein the inner layer board structure and the outer layer board structure are both rectangular, and the positioning portions in the inner layer board structure are arranged at four corners of the rectangle .
The LCP substrate according to claim 7, wherein the outer layer board structure is provided with a window, and the window is arranged opposite to the positioning portion, so that the positioning portion can be exposed from the window. .
The LCP substrate of claim 9, wherein the LCP substrate has a width of 250 mm, a length of 250 mm to 500 mm, and a distance between the edge of the window and the edge of the LCP substrate is greater than 10 mm.