WO2021249397A1

WO2021249397A1 - Circuit board, method for manufacturing circuit board, and electronic device

Info

Publication number: WO2021249397A1
Application number: PCT/CN2021/098925
Authority: WO
Inventors: 尚迎春
Original assignee: 中兴通讯股份有限公司
Priority date: 2020-06-12
Filing date: 2021-06-08
Publication date: 2021-12-16
Also published as: CN113811066A

Abstract

The embodiments of the present application disclose a circuit board, a method for manufacturing a circuit board, and an electronic device, belonging to the field of optical interconnection propagation. The circuit board comprises N layers, N being a natural number equal to or greater than 2. The circuit board comprises: a groove provided on the ith layer of the circuit board, and an optical interconnection structure being placed in the groove; wherein i is a natural number equal to or greater than 1, and less than or equal to N, and there are one or more values for i.

Description

Circuit board, circuit board manufacturing method and electronic equipment

Cross-references to related applications

This application is based on a Chinese patent application with an application number of 202010535294.3 and an application date of June 12, 2020, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby incorporated into this application by way of introduction.

Technical field

The embodiments of the present application relate to the field of optical interconnection propagation, and in particular, to a circuit board, a manufacturing method of the circuit board, and electronic equipment.

Background technique

With the growing demand for the Internet of Everything, the Internet has developed more and more rapidly, and a large number of services are transferred instantly between different sites. These have put forward higher and higher requirements for the switching capacity of the switching equipment in the network. With the increase in the signal transmission rate of the circuit board, when the electrical signal is transmitted inside the switching device, the loss of the electrical signal is too large, and the internal connection of the normal circuit board structure cannot be realized. Therefore, optical interconnection has become a choice .

Summary of the invention

The embodiment of the present application provides a circuit board, the circuit board includes N layers, where N is a natural number greater than 2 or equal to 2, including: a groove is provided on the i-th layer of the circuit board, and an optical interconnection structure is placed in the groove ; Among them, i is a natural number greater than 1 or equal to 1, and less than N or equal to N, and the value of i is one or more.

The embodiment of the present application also provides a method for manufacturing a circuit board. The circuit board includes N layers. The process of forming the i-th layer of the circuit board includes: forming a groove on the i-th layer, and placing the optical interconnection structure In the groove; where N and i are natural numbers, N is greater than or equal to 2, i is greater than or equal to 1 and less than or equal to N, and the value of i is one or more.

The embodiment of the present application also provides an electronic device provided with the circuit board as in the foregoing embodiment, including: a conductive module for transmitting electrical signals; and a light guide module provided in the conductive module for transmitting optical signals.

Description of the drawings

FIG. 1 is a schematic diagram of a three-dimensional structure of a circuit board provided by the first embodiment of the present application.

2 to 7 are schematic diagrams of the three-dimensional structure corresponding to each step of the circuit board manufacturing method provided by the first embodiment of the present application.

FIG. 8 is a schematic diagram of a three-dimensional structure of a circuit board provided by a second embodiment of the present application.

9 to 12 are schematic diagrams of the three-dimensional structure corresponding to each step of the circuit board manufacturing method provided by the second embodiment of the present application.

detailed description

In the optical interconnection scheme, a layer of optical interconnection structure or multilayer optical interconnection structure is fabricated on the circuit board, and the fabricated one or more layers of optical interconnection structure are located between the original circuit board laminate structure, that is, in the circuit board The conductive layer (such as the copper layer) and the non-conductive base layer are independent of the optical interconnection layer and will not appear together in a certain layer. The optical interconnection structure includes an optical core for transmitting optical signals and a cladding layer for reflecting the optical signals to wrap the optical core.

However, the material difference between the optical interconnection structure layer produced by the above solution and other layers of the circuit board is too large. Because the optical interconnection structure is located in the circuit board laminate structure, and the material difference causes the optical interconnection structure and other layers of the circuit board to suffer The different stresses make the optical interconnection structure and the original circuit board located on the upper and lower layers of the optical interconnection structure suffer too much stress difference, which causes the overall circuit board to be easily warped and leads to the optical waveguide lines in the optical interconnection structure fragile.

In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the various embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, a person of ordinary skill in the art can understand that in each embodiment of the present application, many technical details are proposed for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solution claimed in this application can be realized. The following divisions of the various embodiments are for convenience of description, and should not constitute any limitation to the implementation of the present application, and the various embodiments may be combined with each other under the premise of no contradiction.

The first embodiment of the present application relates to a circuit board. The circuit board includes N layers, where N is a natural number greater than 2 or equal to 2, including: a groove is provided on the i-th layer of the circuit board, and an optical interconnection structure is placed in the groove ; Among them, i is a natural number greater than 1 or equal to 1, and less than N or equal to N, and the value of i is one or more. In this embodiment, the value of i is one, that is, this embodiment takes the formation of an optical interconnection structure in the circuit board as an example for illustration, and in this embodiment, N is a natural number greater than 2, and i is greater than 1, and less than the natural number of N, the i-th layer of the groove for placing the optical interconnection structure is not located on the bottom and top layers of the laminated structure, so that the circuit board has a certain protective effect on the optical interconnection structure.

The circuit board involved in this embodiment will be described in detail below with reference to FIGS. 1 to 7.

The circuit board includes N layers, where N is a natural number greater than 2 or equal to 2. Referring to FIG. 1, FIG. 1 is a three-dimensional schematic diagram of the N-layer circuit board provided by the first embodiment of the application. The structure is taken as an example for illustration, that is, N is 3. In an example, the circuit board 10 in FIG. 1 is a circuit board substrate 101, a conductive layer 102, and an interlayer isolation layer 103 in order from bottom to top.

In order to facilitate understanding and description, Figure 2-7 can be regarded as the disassembly diagram of the circuit board and the schematic diagram of the optical interconnection structure on the i-th layer of the circuit board. The following will combine the disassembly diagram of the circuit board to compare the circuit The board is explained in detail.

Referring to FIG. 2, a circuit board substrate 101 is provided.

It should be noted that in this embodiment, the circuit board substrate 101 is described as a single-layer structure, which does not constitute a limitation to this embodiment. In other embodiments, the circuit board substrate may also adopt a laminated structure, such as a circuit. The board substrate may be a printed circuit board (PCB) that already contains multiple copper layers, and the top layer of the circuit board substrate may be formed of a polypropylene (PP) board.

Referring to FIG. 3, there is a conductive layer 102 on the circuit board substrate 10.

In this embodiment, the conductive layer 102 is formed of metallic copper, which has good conductivity and low cost. In other embodiments, the conductive layer may also be formed of other conductive materials, such as silver and tungsten.

Wherein, the thickness of the conductive layer 102 may be 0.5 mm-2.0 mm; for example, 0.8 mm, 1 mm, or 1.6 mm.

Referring to FIG. 4, a groove 201 is provided in the conductive layer 102, and the groove 201 is used to place the optical interconnection structure.

The groove 201 may be a groove penetrating the conductive layer 102 (that is, the groove 201 is provided in the form of a through hole), or it may be an opening on one side of the conductive layer 102 (that is, the groove 201 is provided in the form of a blind hole).

It should be noted that if the groove 201 is a groove penetrating the conductive layer 102, the thickness of the conductive layer 102 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm; if the groove 201 For the opening on one side of the conductive layer 102, the thickness of the groove 201 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm. The thickness of the groove 201 is smaller than the thickness of the conductive layer 102. Since the thickness of the groove 201 in the conductive layer 102 is greater than the thickness of the optical interconnection structure, when the optical interconnection structure is located in the conductive layer 102, the height of the top surface of the optical interconnection structure is lower than the height of the top surface of the conductive layer 102, and the conductive layers 102 are opposed to each other. The optical interconnection structure therein can play a protective role to avoid crushing the optical interconnection structure during the process of making the circuit board structure.

In this embodiment, the conductive layer 102 is used as the i-th layer (i=2) to form the groove 201. In this embodiment, the i-th layer of the circuit board is provided with a groove. In other embodiments, the i-th layer Any layer in the circuit board structure can be used, including interlayer isolation layers and conductive layers.

Since the conductive layer 102 is taken as an example in this embodiment, conductive lines are formed on the conductive layer 102, and the conductive lines are used to transmit electrical signals, so that the conductive layer 102 where the optical interconnection structure 202 is located can transmit optical signals and electrical signals at the same time. In other words, if the i-th layer where the optical interconnection structure is located is a conductive layer, a conductive circuit is made on the remaining conductive layer, so that the i-th layer where the optical interconnection structure is located can simultaneously transmit optical signals and electrical signals.

Referring to FIG. 5, an optical interconnection structure 202 is placed in the groove 201.

In some cases, the optical interconnection structure 202 includes multiple optical lines to realize optical signal transmission between multiple points. The optical lines may be made of flexible waveguides or bare optical fibers. In this embodiment, the shape of the optical interconnection structure 202 shown in FIG. 5 is taken as an example for illustration, which does not constitute a limitation to this embodiment. In other embodiments, the optical interconnection structure may adopt a linear type, etc., but as long as it conforms to this embodiment. The embedding of the optical interconnection structure 202 into the circuit board structure in the application embodiment should fall within the protection scope of this application.

In some cases, in this embodiment, the size of the groove 201 is consistent with the size of the optical interconnection structure, that is, the shape of the groove 201 is set according to the shape of the optical interconnection structure, and the shape of the groove 201 is the same as that of the optical interconnection structure. The shape is: the width of an optical path, and/or an area corresponding to at least one optical path. The optical interconnection structure 202 is positioned by arranging the groove 201 with the same size as the optical interconnection structure 202. In addition, the width at any position of the groove 201 is greater than the width at any position of the corresponding optical interconnection structure 202, which facilitates the placement of the optical interconnection structure in the groove 201. In some cases, grooves are formed in any layer of the circuit board. If the layer is a conductive layer, such as a copper layer, the grooves can be formed by applying green oil and then etching with liquid; if it is a non-conductive base layer , The groove can be formed in the form of a drill bit electric drill. The size of the groove can be the width of a light path, such as within 1mm, or a piece of area, such as an area of 50mmX80mm, or a combination thereof.

Since the width of any position of the groove 201 in this embodiment is greater than the width of any position of the corresponding optical interconnection structure 202, after the optical interconnection structure 202 is placed in the groove 201, there is a gap between the optical interconnection structure 202 and the groove 201, Therefore, fillers need to be added to fill the gaps. In this embodiment, the material of the fillers includes flexible materials, such as fixing glue. Fill the gap between the optical interconnection structure 202 and the groove 201 with filler to fix the optical interconnection structure 202, avoid collision between the optical interconnection structure 202 and the groove 201 due to the existence of the gap, thereby avoiding the optical interconnection structure 202 Be injured. If the filler is formed of a liquid material, the formation of the interlayer isolation layer 103 needs to be performed after the filler is cured.

In this embodiment, it can be seen from the above description that the width of the groove 201 is greater than the width of the optical interconnection structure, and the thickness of the conductive layer (the i-th layer) is greater than the thickness of the optical interconnection structure; in other embodiments, it only needs to satisfy The width of the groove 201 is greater than the width of the optical interconnection structure, or the thickness of the i-th layer is greater than the thickness of the optical interconnection structure. For example, in one example, it is only necessary that the width of the groove 201 is greater than that of the optical interconnection structure. The width is sufficient; in another example, it only needs to satisfy that the thickness of the i-th layer is greater than the thickness of the optical interconnection structure.

It should be noted that the end of the optical interconnection structure 202 may protrude outside the groove 201, or may only be located inside the groove 201. The embodiment of the present application does not limit the position of the end of the optical interconnection structure 202.

Referring to FIG. 6, there is an interlayer isolation layer 103 on top of the conductive layer 102.

In some cases, the interlayer isolation layer 103 can be formed by placing a PP sheet on top of the conductive layer 102 for lamination. The interlayer isolation layer 103 is used to prevent the conductive layer 102 from transmitting electrical signals and signals between other layers of the circuit board. Crosstalk; In addition, the interlayer isolation layer 103 seals the groove 201 for fixing and protecting the optical interconnection structure.

Referring to FIG. 7, it further includes: an optical interconnection extension 203 for extending the end of the optical interconnection structure to the outside of the circuit board. In this embodiment, the material of the optical interconnection epitaxy 203 is the same as that of the optical interconnection structure 202. The optical interconnection epitaxy 203 extends the end of the optical interconnection structure so that part of the optical lines of the optical interconnection structure 202 extends to the circuit. Outside the board, it is convenient for the optical interconnection structure 202 to connect to external devices. In other embodiments, the material of the optical interconnection epitaxy may be inconsistent with the material of the optical interconnection structure, but it is necessary to ensure the signal transmission between the optical interconnection epitaxy and the optical interconnection structure.

In addition, this embodiment takes N=3 and i=2 as examples. It should be noted that in other embodiments, N can be any natural number in 2/4/5/6..., and i can be greater than or equal to 1, and less than or equal to the natural number of N.

In this embodiment, a groove is formed in any layer of the circuit board, and the optical interconnection structure is placed in the groove, that is, there is no need to provide an additional layer or multiple layers of optical interconnection structure in order to provide the optical interconnection structure in the circuit board; The optical interconnection structure does not change the laminated structure of the circuit board, avoiding the excessive stress difference between the optical interconnection structure and the circuit board structure caused by the direct laying of one or more layers of the optical interconnection structure, which in turn leads to the formation of the optical interconnection The structure has problems such as warping and fragility, thereby improving the reliability of the optical interconnection structure.

In addition, since the shape of the groove and the optical interconnection structure are the same, the space required to form the groove in the i-th layer is smaller, so that the material of the i-th layer where the optical interconnection structure is placed has a smaller change (the i-th layer in this embodiment) Including the structure of the original circuit board and the grooves for placing the optical interconnection structure, compared with the i-th layer directly provided with the optical interconnection layer, the material change with the original circuit board structure is small), the stress change is small, thereby further avoiding The optical interconnection structure has problems such as warpage and fragility to ensure the reliability of the optical interconnection structure.

The second embodiment of the present application relates to a circuit board. This embodiment is roughly the same as the first embodiment. The difference from the first embodiment is that in this embodiment, the value of i is multiple, that is, multiple light sources are formed. The interconnection structure is used for the transmission of optical signals.

In this embodiment, the value of i is multiple, that is, this embodiment takes the formation of multiple optical interconnection structures in the circuit board as an example for illustration. It should be noted that when the value of i is multiple natural numbers, the value of i is a discontinuous natural number. In an example, if i takes the value 5, then i cannot take 4 and 6 any more. The purpose of this is that when there are multiple layers in the circuit board used to form grooves for placing the optical interconnection structure, the i-th layer used to form the grooves is not continuous, and in this embodiment, N is a natural number greater than 2. i is a natural number greater than 1 and less than the N. The i-th layer of the groove for placing the optical interconnection structure is not located on the bottom and top layers of the laminated structure, so that the circuit board has a certain protective effect on the optical interconnection structure.

The circuit board involved in this embodiment will be described in detail below with reference to FIGS. 8 to 12.

The circuit board includes N layers, where N is a natural number greater than 2 or equal to 2. Referring to FIG. 8, FIG. 8 is a three-dimensional schematic diagram of the N-layer circuit board provided by the second embodiment of the application. Take the structure as an example for illustration, that is, N is 6. In an example, the circuit board 30 in Figure 8 is a circuit board substrate 301, a first conductive layer 302, a first insulating layer 303, and a second conductive layer in order from bottom to top. 304, a second insulating layer 305, and a third insulating layer 306.

In order to facilitate understanding and description, Figures 9-12 can be regarded as the disassembly diagram of the circuit board and the schematic diagram of the structure of the optical interconnection structure on the i-th layer of the circuit board. The following will combine the disassembly diagram of the circuit board to compare the circuit The board is explained in detail.

Referring to FIG. 9, in this embodiment, the circuit board substrate 301 is the same as the circuit board substrate in the first embodiment, and the first conductive layer 302 and the second conductive layer 304 are the same as the conductive layer in the first embodiment. An insulating layer 303, a second insulating layer 305, and a third insulating layer 306 have the same material as the interlayer isolation layer in the first embodiment. For related content, refer to the description in the first embodiment. For the same parts as the first embodiment, details are not repeated in this embodiment.

On top of the first insulating layer 303, a second conductive layer 304 and a second insulating layer 305 are further included.

Referring to FIG. 10, a groove 201 is provided in the second insulating layer 305, and the groove 201 is used to place the optical interconnection structure.

Wherein, the groove 201 may be a groove penetrating the second insulating layer 305 or an opening on the side of the second insulating layer 305.

It should be noted that if the groove 201 is a groove penetrating the second insulating layer 305, the thickness of the second insulating layer 305 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm. If the groove 201 is an opening on the side of the second insulating layer 305, the thickness of the groove 201 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm, etc. Correspondingly, the second insulating layer The thickness of 305 needs to be larger than the thickness of groove 201. Since the thickness of the groove 201 in the second insulating layer 305 is greater than the thickness of the optical interconnection structure, when the optical interconnection structure is located in the second insulating layer 305, the height of the top surface of the optical interconnection structure is lower than the height of the top surface of the second insulating layer 305 The second insulating layer 305 can protect the optical interconnection structure placed therein to avoid crushing the optical interconnection structure during the process of making the circuit board structure.

In this embodiment, the first conductive layer 302 and the second insulating layer 305 are used as the i-th layer (i=2, 5) to form the groove 201. In this embodiment, the groove 201 is provided in the i-th layer of the circuit board. At the same time, in order to show that the i-th layer may be a conductive layer or an interlayer isolation layer, in other embodiments, the i-th layer may be any layer in the circuit board structure, including an interlayer isolation layer and a conductive layer.

Referring to FIG. 11, an optical interconnection structure 202 is placed in the groove 201.

Referring to FIG. 12, there is a third insulating layer 306 on top of the second insulating layer 305.

In some cases, the third insulating layer 306 can be formed by placing a PP sheet on top of the second insulating layer 305 for lamination. The third insulating layer 306 is used to prevent the optical signal transmitted by the optical interconnection structure 202 from being connected to other layers of the circuit board. Signal crosstalk between; in addition, the third insulating layer 306 seals the groove 201 for fixing and protecting the optical interconnection structure.

In addition, it also includes an optical interconnection extension 203, which is used to extend the end of the optical interconnection structure to the outside of the circuit board. The material of the optical interconnection epitaxy 203 is the same as that of the optical interconnection structure 202. The optical interconnection epitaxy 203 extends the end of the optical interconnection structure so that part of the optical lines of the optical interconnection structure 202 extends outside the circuit board to facilitate The optical interconnection structure 202 is connected to an external device.

In addition, in this embodiment, a plurality of optical interconnection structures are formed for optical signal transmission, and the i-th layer of the optical interconnection structure is provided with grooves that are not located on the bottom and top layers of the laminated structure, so that the circuit board is opposite to the optical interconnection structure. Has a certain protective effect.

It is not difficult to find that this embodiment is an apparatus embodiment related to the first embodiment, and this embodiment can be implemented in cooperation with the first embodiment. The related technical details mentioned in the first embodiment are still valid in this embodiment, and in order to reduce repetition, they will not be repeated here. Correspondingly, the related technical details mentioned in this embodiment can also be applied to the first embodiment.

The third embodiment of the present application relates to an electronic device provided with the circuit board provided in the above-mentioned first or second embodiment, including: a conductive module for transmitting electrical signals, a light guide module arranged in the conductive module, Used to transmit optical signals.

The conductive module is the original circuit board structure in the circuit board and is used to transmit electrical signals.

The circuit board includes N layers, and N is a natural number greater than 2 or equal to 2. Referring to FIG. 1, the circuit board 10 in this embodiment is illustrated with a three-layer structure as an example, that is, N is 3. In an example, in FIG. The circuit board 10 includes a circuit board substrate 101, a conductive layer 102, and an interlayer isolation layer 103 in order from bottom to top.

Since the conductive layer 102 is taken as an example in this embodiment, conductive lines are formed on the conductive layer 102, and the conductive lines are used to transmit electrical signals.

The light guide module is an optical interconnection structure placed in the original circuit board structure for transmitting optical signals.

It should be noted that if the groove 201 is a groove penetrating the conductive layer 102, the thickness of the conductive layer 102 needs to be 0.5 mm-1.0 mm larger than the thickness of the optical interconnection structure, such as 0.6 mm or 0.8 mm. If the groove 201 is an opening on one side of the conductive layer 102, the thickness of the groove 201 needs to be 0.5 mm-1.0 mm larger than the thickness of the optical interconnection structure, such as 0.6 mm or 0.8 mm. The thickness of the groove 201 is smaller than the thickness of the conductive layer 102. Since the thickness of the groove 201 in the conductive layer 102 is greater than the thickness of the optical interconnection structure, when the optical interconnection structure is located in the conductive layer 102, the height of the top surface of the optical interconnection structure is lower than the height of the top surface of the conductive layer 102, and the conductive layers 102 are opposed to each other. The optical interconnection structure therein can play a protective role to avoid crushing the optical interconnection structure during the process of making the circuit board structure.

The optical interconnection structure is used to transmit optical signals, and since the conductive layer 102 is taken as an example in this embodiment, conductive lines are formed on the conductive layer 102, and the conductive lines are used to transmit electrical signals, so that the conductive layer 102 where the optical interconnection structure 202 is located can be simultaneously Transmission of optical and electrical signals. In other words, if the i-th layer where the optical interconnection structure is located is a conductive layer, a conductive circuit is made on the remaining conductive layer, so that the i-th layer where the optical interconnection structure is located can simultaneously transmit optical signals and electrical signals.

It is not difficult to find that this embodiment is a device embodiment related to the application of the first embodiment or the second embodiment, and this embodiment can be implemented in cooperation with the first embodiment or the second embodiment. The related technical details mentioned in the first embodiment or the second embodiment are still valid in this embodiment, and in order to reduce repetition, they will not be repeated here. Correspondingly, the related technical details mentioned in this embodiment can also be applied to the first embodiment or the second embodiment.

The fourth embodiment of the present application relates to a manufacturing method of a circuit board, which is used to form the above-mentioned circuit board.

The manufacturing method of the circuit board provided by the embodiment of the present application will be described in detail below in conjunction with FIG. 1 to FIG. 7.

The circuit board includes N layers. The process of forming the i-th layer of the circuit board includes: forming a groove on the i-th layer and placing the optical interconnection structure in the groove; where N and i are both natural numbers, and N is greater than Or equal to 2, i is greater than or equal to 1 and less than or equal to N, and the value of i is one or more. In this embodiment, the value of i is one, that is, this embodiment takes the formation of an optical interconnection structure in the circuit board as an example for illustration, and in this embodiment, N is a natural number greater than 2, and i is greater than 1, and less than the natural number of N, the i-th layer of the groove for placing the optical interconnection structure is not located on the bottom and top layers of the laminated structure, so that the circuit board has a certain protective effect on the optical interconnection structure.

Referring to FIG. 1, the circuit board 10 in this embodiment is illustrated with a three-layer structure as an example, that is, N is 3. In one example, the circuit board 10 in FIG. 1 is a circuit board substrate 101 and a conductive layer from bottom to top. 102 and interlayer isolation layer 103.

For ease of understanding and description, refer to Figure 2 to Figure 7 for the formation process of the circuit board, as follows:

Referring to FIG. 2, a circuit board substrate 101 is provided. It should be noted that, in this embodiment, the circuit board substrate 101 is described as a single-layer structure, which does not constitute a limitation to this embodiment.

Referring to FIG. 3, a conductive layer 102 is formed on the circuit board substrate 10.

Referring to FIG. 4, a groove 201 is formed in the conductive layer 102, and the groove 201 is used to place the optical interconnection structure.

It should be noted that if the groove 201 is a groove penetrating the conductive layer 102, the thickness of the conductive layer 102 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm; if the groove 201 For the opening on one side of the conductive layer 102, the thickness of the groove 201 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm. The thickness of the groove 201 is smaller than the thickness of the conductive layer 102. Since the thickness of the groove 201 in the conductive layer 102 is greater than the thickness of the optical interconnection structure, when the optical interconnection structure is located in the conductive layer 102, the height of the top surface of the optical interconnection structure is lower than the height of the top surface of the conductive layer 102, and the conductive layers 102 are opposed to each other. The optical interconnection structure therein can play a certain protective role.

In this embodiment, the conductive layer 102 is used as the i-th layer (i=2) to form the groove 201. In this embodiment, the groove 201 is formed in the i-th layer of the circuit board. In other embodiments, the i-th layer Any layer in the circuit board structure can be used, including interlayer isolation layers and conductive layers.

Referring to FIG. 5, the optical interconnection structure 202 is placed in the groove 201.

The optical interconnection structure 202 includes multiple optical lines to realize optical signal transmission between multiple points. The optical lines can be made of flexible waveguides or bare optical fibers. In this embodiment, the shape of the optical interconnection structure 202 shown in FIG. 5 is taken as an example for description, which does not constitute a limitation to this embodiment.

In some cases, in this embodiment, the size of the groove 201 is consistent with the size of the optical interconnection structure 202, that is, the shape of the groove 201 is set according to the shape of the optical interconnection structure, and the shape of the groove 201 is the same as that of the optical interconnection structure. The shape of is: the width of an optical path, and/or an area corresponding to at least one optical path. The width at any position of the groove 201 is correspondingly larger than the width at any position of the optical interconnection structure 202. The optical interconnection structure is positioned by arranging the groove 201 with the same size as the optical interconnection structure 202. The width of the groove 201 is greater than the width of the optical interconnection structure 202, so that the optical interconnection structure can be placed in the groove 201 conveniently.

At the same time, since the width of any position of the groove 201 in this embodiment is greater than the width of any position of the corresponding optical interconnection structure 202, after the optical interconnection structure 202 is placed in the groove 201, there is a gap between the optical interconnection structure 202 and the groove 201. Therefore, fillers need to be added to fill the gaps. In this embodiment, the material of the fillers includes flexible materials, such as fixing glue. Fill the gap between the optical interconnection structure 202 and the groove 201 with filler to fix the optical interconnection structure 202 to avoid the gap between the optical interconnection structure 202 and the groove 201 during the use of the optical interconnection structure 202 In this way, the optical interconnection structure 202 is prevented from being damaged. If the filler is formed of a liquid material, the formation of the interlayer isolation layer 103 needs to be performed after the filler is cured.

In addition, this embodiment shows the conductive layer 102 as an example. A groove 201 is formed in the conductive layer 102 to prevent the optical interconnection structure 202. Before placing the optical interconnection structure 202 in the groove 201, it also includes: forming on the conductive layer 102 The conductive lines transmit electrical signals, so that the conductive layer 102 where the optical interconnection structure 202 is located can transmit optical signals and electrical signals at the same time. In other words, if the i-th layer where the optical interconnection structure is located is a conductive layer, a conductive circuit is made on the remaining conductive layer, so that the i-th layer where the optical interconnection structure is located can simultaneously transmit optical signals and electrical signals.

Referring to FIG. 6, an interlayer isolation layer 103 is formed on top of the conductive layer 102.

Referring to FIG. 7, after forming the interlayer isolation layer 103, the optical interconnection epitaxy 203 is formed to extend the end of the optical interconnection structure to the outside of the circuit board. In this embodiment, the material of the optical interconnection epitaxy 203 and the optical interconnection structure The material of 202 is the same. The optical interconnection extension 203 extends the end of the optical interconnection structure, so that part of the optical lines of the optical interconnection structure 202 extends outside the circuit board, so that the optical interconnection structure 202 can be connected to external devices.

In other embodiments, the step of forming the optical interconnection epitaxy may be immediately after placing the optical interconnection structure in the groove. This embodiment does not limit the implementation time of the step of forming the optical interconnection epitaxy. In the application process, It can be adjusted accordingly according to the production environment. And the material of the optical interconnection epitaxy may be inconsistent with the material of the optical interconnection structure, but it is necessary to ensure the signal transmission between the optical interconnection epitaxy and the optical interconnection structure.

The division of the steps of the various methods above is only for clarity of description. When implemented, it can be combined into one step or some steps can be split into multiple steps, as long as they include the same logical relationship, they are all within the scope of protection of this patent. ; Adding insignificant modifications to the algorithm or process or introducing insignificant design, but not changing the core design of the algorithm and process are within the scope of protection of the patent.

Since the first embodiment corresponds to this embodiment, this embodiment can be implemented in cooperation with the first embodiment. The related technical details mentioned in the first embodiment are still valid in this embodiment, and the technical effects that can be achieved in the first embodiment can also be achieved in this embodiment. In order to reduce repetition, details are not repeated here. Correspondingly, the related technical details mentioned in this embodiment can also be applied to the first embodiment.

The fifth embodiment of the present application relates to a method for manufacturing a circuit board. This embodiment is roughly the same as the fourth embodiment. The difference from the fourth embodiment is that there are multiple optical interconnection structures formed in this embodiment. Multiple optical interconnection structures are used for optical signal transmission.

The manufacturing method of the circuit board provided by the embodiment of the present application will be described in detail below in conjunction with FIG. 8 to FIG. 12.

The circuit board includes N layers. The process of forming the i-th layer of the circuit board includes: forming a groove on the i-th layer and placing the optical interconnection structure in the groove; where N and i are both natural numbers, and N is greater than Or equal to 2, i is greater than or equal to 1 and less than or equal to N, and the value of i is one or more.

Referring to FIG. 8, the circuit board 30 in this embodiment takes a 6-layer structure as an example for illustration, that is, N is 6. In an example, the circuit board 30 in FIG. The conductive layer 302, the first insulating layer 303, the second conductive layer 304, the second insulating layer 305, and the third insulating layer 306.

For ease of understanding and description, refer to Figure 9 to Figure 12 for the formation process of the circuit board, as follows:

In this embodiment, the circuit board substrate 301 is the same as the circuit board substrate in the third embodiment, the first conductive layer 302 and the second conductive layer 304 are the same as the conductive layer in the third embodiment, and the first insulating layer 303 The second insulating layer 305 and the third insulating layer 306 have the same material as the interlayer isolation layer in the third embodiment. For related content, refer to the description in the third embodiment, and the same parts as the third embodiment will not be repeated in this embodiment.

Referring to FIG. 9, the method flow of the circuit board substrate 301, the first conductive layer 302, the first insulating layer 303, the groove in the first conductive layer 302, and the optical interconnection structure 201 refers to the third embodiment. On this basis, After forming the first insulating layer 303, a second conductive layer 304 and a second insulating layer 305 are sequentially formed on top of the first insulating layer 303.

Referring to FIG. 10, a groove 201 is formed in the second insulating layer 305, and the groove 201 is used for placing the optical interconnection structure.

It should be noted that if the groove 201 is a groove penetrating the second insulating layer 305, the thickness of the second insulating layer 305 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm; If the groove 201 is an opening on the side of the second insulating layer 305, the thickness of the groove 201 needs to be 0.5mm-1.0mm larger than the thickness of the optical interconnection structure, such as 0.6mm or 0.8mm, etc. Correspondingly, the second insulating layer The thickness of 305 needs to be larger than the thickness of groove 201. Since the thickness of the groove 201 in the second insulating layer 305 is greater than the thickness of the optical interconnection structure, when the optical interconnection structure is located in the second insulating layer 305, the height of the top surface of the optical interconnection structure is lower than the height of the top surface of the second insulating layer 305 The second insulating layer 305 can protect the optical interconnection structure placed therein to a certain extent.

In this embodiment, the first conductive layer 302 and the second insulating layer 305 are used as the i-th layer (i=2, 5) to form the groove 201, which is an example of the groove formed in the i-th layer of the circuit board in this embodiment . At the same time, in order to show that the i-th layer may be a conductive layer or an interlayer isolation layer, in other embodiments, the i-th layer may be any layer in the circuit board structure, including an interlayer isolation layer and a conductive layer.

Referring to FIG. 11, the optical interconnection structure 202 is placed in the groove 201.

Referring to FIG. 12, a third insulating layer 306 is formed on top of the second insulating layer 305.

After the third insulating layer 306 is formed, the optical interconnection epitaxy 203 is formed to extend the end of the optical interconnection structure to the outside of the circuit board. In this embodiment, the material of the optical interconnection epitaxy 203 is the same as the material of the optical interconnection structure 202 , The end of the optical interconnection structure is extended, so that part of the optical lines of the optical interconnection structure 202 extend outside the circuit board, so that the optical interconnection structure 202 can be connected to an external device. In addition, in other embodiments, the step of forming the optical interconnection epitaxy may be immediately after placing the optical interconnection structure in the groove. This embodiment does not limit the implementation time of the step of forming the optical interconnection epitaxy. , You can adjust accordingly according to the production environment.

Since the second embodiment corresponds to this embodiment, this embodiment can be implemented in cooperation with the second embodiment. The related technical details mentioned in the second embodiment are still valid in this embodiment, and the technical effects that can be achieved in the second embodiment can also be achieved in this embodiment. In order to reduce repetition, details are not repeated here. Correspondingly, the related technical details mentioned in this embodiment can also be applied in the second embodiment.

Part of the embodiments of the application have been described above with reference to the accompanying drawings, which does not limit the scope of rights of the application. Any modification, equivalent replacement and improvement made by those skilled in the art without departing from the scope and essence of the application shall fall within the scope of the rights of the application.

Claims

A circuit board includes N layers, where N is a natural number greater than or equal to 2, and includes:

A groove is provided on the i-th layer of the circuit board, and an optical interconnection structure is placed in the groove;

Wherein, the i is a natural number greater than or equal to 1 and less than or equal to the N, and the value of i is one or more.
The circuit board according to claim 1, wherein the shape of the groove is consistent with the shape of the optical interconnection structure.
3. The circuit board according to claim 2, wherein the shape of the groove and the shape of the optical interconnection structure are: the width of an optical path, and/or an area corresponding to at least one optical path.
The circuit board according to claim 1, wherein the width of the groove is greater than the width of the optical interconnection structure, and/or the thickness of the i-th layer is greater than the thickness of the optical interconnection structure.
The circuit board according to claim 1 or 4, wherein there is a gap between the optical interconnection structure and the groove, and the circuit board further comprises a filler, and the filler is used to fill the gap.
The circuit board according to claim 5, wherein the material of the filler includes a flexible material.
The circuit board according to claim 1, wherein the i-th layer includes a conductive layer or an interlayer isolation layer.
8. The circuit board according to claim 7, wherein the i-th layer is a conductive layer, the conductive layer is formed with conductive lines, and the conductive lines are used to transmit electrical signals.
4. The circuit board according to claim 1, further comprising: an optical interconnection extension for extending the end of the optical interconnection structure to the outside of the circuit board.
An electronic device, wherein the circuit board according to any one of claims 1 to 9 is provided, comprising:

Conductive module, used to transmit electrical signals;

The light guide module arranged in the conductive module is used to transmit optical signals.
A method for manufacturing a circuit board, the circuit board includes N layers, wherein the process of forming the i-th layer of the circuit board includes:

Forming a groove on the i-th layer, and placing the optical interconnection structure in the groove;

Wherein, the N and i are both natural numbers, the N is greater than or equal to 2, the i is greater than or equal to 1 and less than or equal to the N, and the value of i is one or more.
11. The manufacturing method of the circuit board according to claim 11, wherein the shape of the groove formed on the i-th layer is consistent with the shape of the optical interconnection structure.
The method of manufacturing a circuit board according to claim 12, wherein the shape of the groove formed on the i-th layer and the shape of the optical interconnection structure are: the width of an optical path, and/or at least An area corresponding to a light path.
The method of manufacturing a circuit board according to claim 11, wherein the width of the groove formed on the i-th layer is greater than the width of the optical interconnection structure, and/or the width of the i-th layer formed The thickness is greater than the thickness of the optical interconnection structure.
The method for manufacturing a circuit board according to claim 11 or 14, wherein after the optical interconnection structure is placed in the groove, there is a gap between the optical interconnection structure and the groove, and Including: adding filler to the gap.
11. The method of manufacturing a circuit board according to claim 11, wherein the i-th layer comprises a conductive layer or an interlayer isolation layer.
The method of manufacturing a circuit board according to claim 16, wherein the i-th layer is a conductive layer, and a conductive circuit is formed on the conductive layer, and the conductive circuit is used to transmit electrical signals.
The method of manufacturing a circuit board according to claim 11, wherein after placing the optical interconnection structure in the groove, further comprising: forming an optical interconnection extension to extend the end of the optical interconnection structure to The outside of the circuit board.