CN112867226B

CN112867226B - High-frequency transmission circuit board and manufacturing method thereof

Info

Publication number: CN112867226B
Application number: CN201911184694.8A
Authority: CN
Inventors: 何明展; 沈芾云; 钟福伟; 郭宏艳
Original assignee: Avary Holding Shenzhen Co Ltd; Qing Ding Precision Electronics Huaian Co Ltd
Current assignee: Avary Holding Shenzhen Co Ltd; Qing Ding Precision Electronics Huaian Co Ltd
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2022-12-06
Anticipated expiration: 2039-11-27
Also published as: CN112867226A

Abstract

A high-frequency transmission circuit board includes a first circuit substrate; the first circuit substrate comprises a first base material layer and a first conductive circuit layer formed on the first base material layer; a first blind hole is formed in the first base material layer, and a first conductive column is formed in the blind hole; the first conductive circuit layer comprises a first transmission circuit; the first transmission line comprises at least one of a first power supply line and a first control line; the second circuit substrate is formed on the first circuit substrate and comprises a second base material layer and a second conducting circuit layer; a second blind hole is formed in the second base material layer, and a second conductive column is formed in the second blind hole; the second conductive circuit layer comprises a second transmission line, and the second transmission line comprises at least one of a second power supply line and a second control line; the first and second transmission lines are stacked together and connected in parallel by the first or second conductive column. The invention also provides a manufacturing method of the high-frequency transmission circuit board.

Description

High-frequency transmission circuit board and manufacturing method thereof

Technical Field

The invention relates to a multilayer printed circuit board technology, in particular to a high-frequency transmission circuit board and a manufacturing method thereof.

Background

The development of 5G technology is a big trend. The high-pass QTM052 chip is the first choice of the current 5G mobile phone, but the transmission line in the current high-pass QTM052 chip is flattened and needs to be laid out on a motherboard or a battery, so that the flexibility of the transmission line layout space of the high-pass QTM052 chip is weaker than that of a cable line, but a single cable line cannot meet the requirement of multiple transmission lines. In addition, the flattening of the transmission lines results in an increase in the width of the chip, which takes up a large space.

Disclosure of Invention

In view of this, the present invention provides a high frequency transmission circuit board which satisfies the wiring requirement of the transmission line and occupies a small space.

It is also necessary to provide a method of manufacturing the high frequency transmission circuit board as described above.

A high frequency transmission circuit board includes a first circuit substrate; the first circuit substrate comprises a first base material layer and a first conductive circuit layer formed on the first base material layer; at least two first blind holes penetrating through the first base material layer are formed in the first base material layer, and first conductive columns are formed in the blind holes; the first conductive line layer comprises at least two first transmission lines; the second circuit substrate comprises a second base material layer and a second conductive circuit layer formed on the second base material layer; at least two second blind holes penetrating through the second base material layer are formed in the second base material layer, and second conductive columns are formed in the second blind holes; the second conductive circuit layer comprises at least two second transmission lines; the first transmission lines and the corresponding second transmission lines are stacked together and connected in parallel through the first conductive columns or the second conductive columns.

Further, the high-frequency transmission circuit board further includes at least one electromagnetic shielding layer formed on an outermost side of the high-frequency transmission circuit board, and the electromagnetic shielding layer is electrically connected to a transmission line of a circuit substrate of the high-frequency transmission circuit board.

Further, the high-frequency transmission circuit board is divided into two terminal areas and a transmission line area located between the two terminal areas, and the first transmission line and the second transmission line are located in the transmission line area; the electromagnetic shielding layer covers the side of the transmission line region of the high-frequency transmission circuit board.

Further, the high-frequency transmission circuit board further comprises a third circuit substrate formed on the second circuit substrate, and the third circuit substrate comprises a third base material layer and a third conducting circuit layer formed on the third base material layer; at least two third blind holes penetrating through the third base material layer are formed in the third base material layer, and third conductive columns are formed in the third blind holes; the third conductive circuit layer comprises at least two third transmission lines, and the third transmission lines are positioned in the transmission line area; the third transmission line and the corresponding second transmission line are stacked together and connected in parallel with the third conductive column through the third conductive column or the second conductive column.

Furthermore, the first circuit substrate further comprises a signal line and a first grounding line positioned on one side of the signal line; the second circuit substrate further comprises a second ground line; the third circuit substrate further includes a third ground line; the first ground line, the second ground line, and the third ground line are electrically connected to each other through the first conductive pillar, the second conductive pillar, and the third conductive pillar, excluding the first conductive pillar, the second conductive pillar, and the third conductive pillar that electrically connect the first transmission line, the second transmission line, and the third transmission line; the signal line is separated from the first transmission line, the second transmission line and the third transmission line through the first grounding line, the second grounding line and the third grounding line.

Further, the signal line and the electromagnetic shielding layer on the side edge or the first transmission line and the electromagnetic shielding layer on the side edge are spaced apart by the conductive pillar.

Further, the signal line is located on one side of the electromagnetic shielding layer on the side edge, and the first transmission line is located on one side of the electromagnetic shielding layer on the side edge.

Further, the first transmission line comprises at least one of a first power supply line and a first control line; the second transmission line includes at least one of a second power supply line and a second control line.

A manufacturing method of a high-frequency transmission circuit board comprises the following steps: manufacturing a first circuit substrate; the first circuit substrate comprises at least two first transmission lines; manufacturing a second circuit substrate, and pressing the second circuit substrate on the first circuit substrate; the second circuit substrate includes at least two second transmission lines; the first transmission lines and the corresponding second transmission lines are stacked together and connected in parallel through the conductive columns.

Further, the method for manufacturing the first circuit substrate includes the following steps: providing a copper-clad substrate, wherein the copper-clad substrate comprises a first base material layer and a copper foil layer formed on the first base material layer; manufacturing the copper foil layer to form a first conductive circuit layer; the first conductive circuit layer comprises at least two first transmission lines; forming at least two first blind holes on the first base material layer; part of the first transmission line is exposed out of the first blind hole; and respectively filling a conductive material in the first blind hole to form a first conductive column, wherein one end of the first conductive column is electrically contacted with the first transmission line exposed from the first blind hole.

Further, after the step of laminating the second circuit substrate on the first circuit substrate, the method further comprises the steps of: and at least one electromagnetic shielding layer is formed on the outermost side of the high-frequency transmission circuit board, and the electromagnetic shielding layer is electrically connected with the transmission line of the circuit substrate on the outermost side of the high-frequency transmission circuit board.

The high-frequency transmission circuit board comprises at least two circuit substrates, wherein each circuit substrate positioned in a transmission line area comprises at least two transmission lines, the transmission lines positioned in different circuit substrates of the high-frequency transmission circuit board are overlapped together and are connected in parallel through the conductive columns, so that the occupied space of the transmission lines of the high-frequency transmission circuit board can be reduced; 2) The transmission lines positioned in different circuit substrates are overlapped together and are connected in parallel through the conductive columns, so that the resistance of the transmission lines can be reduced, and the loss can be reduced; 3) An electromagnetic shield layer is formed on the periphery of the transmission line region of the high-frequency transmission circuit board, so that electromagnetic interference between the terminal region and the bending region of the high-frequency transmission circuit board and the transmission line region can be prevented.

Drawings

Fig. 1 is a cross-sectional view of a copper-clad substrate according to a preferred embodiment of the invention.

Fig. 2 is a cross-sectional view of the copper foil layer of the copper-clad substrate shown in fig. 1 after a conductive circuit layer is formed.

Fig. 3 is a cross-sectional view of the copper-clad substrate shown in fig. 2 after blind vias are formed in the substrate layer.

Fig. 4 is a cross-sectional view of the conductive post formed in the blind via hole shown in fig. 3 to form the first circuit substrate.

Fig. 5 is a cross-sectional view of the first circuit substrate, the two second circuit substrates and the two third circuit substrates shown in fig. 4 according to the present invention.

Fig. 6 is a cross-sectional view of the first circuit substrate, the two second circuit substrates and the two third circuit substrates shown in fig. 5 stacked and pressed together to form a circuit board stacked body.

Fig. 7 is a cross-sectional view of the circuit board stacked body shown in fig. 6 after a cover film is attached to each of the cover films.

Fig. 8 is a cross-sectional view after a gold plating layer is formed on the transmission line exposed from the opening of the cover film shown in fig. 7.

Fig. 9 is a cross-sectional view of the high-frequency transmission circuit board formed by attaching an electromagnetic shielding layer to the side of the circuit board stacked body in the transmission line region and in the transmission line region shown in fig. 8.

Fig. 10 is a top view of the high frequency transmission circuit board shown in fig. 9.

Fig. 11 is a cross-sectional view of the high frequency transmission circuit board in the bending region connecting the transmission line region and the terminal region provided by the present invention.

Description of the main elements

High-frequency transmission circuit board 100

Terminal area 101

Transmission line region 102

Bending region 103

Copper-clad substrate 10

First base material layer 11

Copper foil layer 12

First conductive line layer 13

Signal line 131

First ground line

132, 136

First

power supply lines

133, 137

First control lines

134, 138

First

blind holes

141, 142

First

conductive posts

151, 152

First circuit substrate 110

Second circuit substrate 120

Second base material layer 21

Second

blind holes

241, 242

Second

conductive posts

251, 252

Second conductive line layer 23

Second ground line

232, 236

Second power supply line 233, 237

Third circuit board 130

Third base material layer 31

Third

blind holes

341, 342

Third

conductive pillars

351, 352

Third conductive line layer 33

Third ground lines

332, 336

Third power supply line 337

Third control line 338

Circuit board stacked body 140

Protective layer 150

Opening 1501

Gold-dissolving layer 160

Electromagnetic shield layer 170

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

In order to further explain the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description will be made on specific embodiments, structures, features and effects of the high frequency transmission circuit board and the manufacturing method thereof provided by the present invention with reference to the accompanying drawings 1-11 and preferred embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1 to 11, the present invention provides a method for manufacturing a high frequency transmission circuit board 100, which includes the following steps:

in step S10, referring to fig. 1-4, a first circuit substrate 110 is fabricated.

The first circuit substrate 110 is divided into two terminal areas 101 and a transmission line area 102 located between the two terminal areas 101.

The first circuit board 110 includes a first substrate layer 11 and a first conductive trace layer 13 formed on the first substrate layer 11.

The material of the first substrate layer 11 may be one of flexible materials such as Polyimide (PI), polyethylene Terephthalate (PET), polyethylene Naphthalate (PEN), polyethylene (PE), teflon (Teflon), liquid Crystal Polymer (LCP), and polyvinyl chloride (PVC).

Specifically, the first conductive line layer 13 includes at least two

signal lines

131 and 135, at least four

first ground lines

132 and 136, at least four first

power supply lines

133 and 137, and at least four

first control lines

134 and 138. At least one signal line 131, at least two first ground lines 132, at least two first power lines 133, and at least two first control lines 134 are located in the terminal area 101. At least one of the signal lines 135, at least two of the first ground lines 136, at least two of the first power lines 137, and at least two of the first control lines 138 are located within the transmission line region 102. At least two of the first power lines 137 and at least two of the first control lines 138 are first transmission lines of the first circuit substrate 110.

In the terminal region 101, every two first ground lines 132 are located on two sides of one signal line 131, two first power lines 133 and two first control lines 134 are located on one side of the first ground line 132, and two first power lines 133 are located between one first ground line 132 and two first control lines 134. In the transmission line region 102, every two first ground lines 135 are located at two sides of one signal line 135, two first power supply lines 137 and two first control lines 138 are located at one side of the first ground line 136, and two first power supply lines 137 are located between one first ground line 136 and two first control lines 138.

The first ground lines 132 on both sides of the signal line 131 are used to prevent electromagnetic interference between two

adjacent signal lines

131 or 135. The

first power lines

133 and 137 are used for connecting a power source (not shown). The

first control lines

134 and 138 are used for connecting an antenna module (not shown).

In this embodiment, the first conductive trace layer 13 further includes a first ground trace 132 on a side of the first control trace 134 away from the signal trace 131, and a first ground trace 136 on a side of the first control trace 138 away from the signal trace 135, so as to better shield the terminal region 101 and the transmission line region 102 from electromagnetic interference.

In this embodiment, the first conductive trace layer 13 includes two signal traces 131, four first ground traces 132, two first power traces 133, two first control traces 134 in the terminal area 101, and two signal traces 135, four first ground traces 136, two first power traces 137, and two first control traces 138 in the transmission line area 102.

At least two first blind holes 141 penetrating through the first substrate layer 11 and located in the terminal region 101, a first conductive pillar 151 filled in the first blind holes 141, at least six first blind holes 142 located in the transmission line region 102, and the first conductive pillar 152 filled in the first blind holes 142 are further formed in the first substrate layer 11. In the terminal region 101, a portion of the first ground line 132 is exposed from the first blind hole 141 and electrically contacts the corresponding first conductive pillar 151. In the transmission line region 102, a portion of the first ground line 136 is exposed from the corresponding first blind via 142 and electrically contacts the corresponding first conductive pillar 152, and a portion of the first power supply line 137 and a portion of the first control line 138 are exposed from the corresponding first blind via 142 and electrically contacts the corresponding first conductive pillar 152.

In the present embodiment, in the terminal region 101, one first blind hole 141 and a corresponding first conductive pillar 151 are further formed in the first base material layer 11 so as to face the first ground line 132 located on the side of the first control line 134 away from the signal line 131. In the transmission line region 102, a first blind via 142 and a corresponding first conductive pillar 152 are further formed on the first substrate layer 11, and the first blind via is opposite to the first ground line 136 located on the side of the first control line 138 away from the signal line 135.

The first

conductive pillars

151 and 152 may be made of a conductive material such as a conductive paste or copper plating.

Referring to fig. 1-4, the method for manufacturing the first circuit substrate 110 includes the following steps:

in step S11, referring to fig. 1, a copper clad substrate 10 is provided.

The copper-clad substrate 10 is divided into two terminal areas 101 and a transmission line area 102 located in the two terminal areas 101.

The copper-clad substrate 10 includes a first substrate layer 11 and a copper foil layer 12 formed on the first substrate layer 11.

Step S12, referring to fig. 2, the copper foil layer 12 is fabricated to form a first conductive trace layer 13.

The first conductive circuit layer 13 includes at least two

signal lines

131 and 135, at least four

first ground lines

132 and 136, at least four

first power lines

133 and 137, and at least four

first control lines

134 and 138. At least one signal line 131, at least two first ground lines 132, at least two first power lines 133, and at least two first control lines 134 are located in the terminal area 101. At least one of the signal lines 135, at least two of the first ground lines 136, at least two of the first power lines 137, and at least two of the first control lines 138 are located within the transmission line region 102. In the terminal region 101, every two first ground lines 132 are located on two sides of one signal line 131, two first power lines 133 and two first control lines 134 are located on one side of the first ground line 132, and two first power lines 133 are located between one first ground line 132 and two first control lines 134. In the transmission line region 102, every two first ground lines 135 are located at two sides of one signal line 135, two first power supply lines 137 and two first control lines 138 are located at one side of the first ground line 136, and two first power supply lines 137 are located between one first ground line 136 and two first control lines 138.

Step S13, referring to fig. 3, at least two first blind holes 141 are formed on the first substrate layer 11 located in the terminal region 101, and at least six first blind holes 142 are formed on the first substrate layer 11 located in the transmission line region 102.

The first

blind holes

141 and 142 penetrate through the first substrate layer 11. In the terminal region 101, a part of the first ground line 132 is exposed from the first blind hole 141. In the transmission line region 102, a part of the first ground line 136, a part of the first power supply line 137, and a part of the first control line 138 are exposed from the corresponding first blind holes 142.

In step S14, referring to fig. 4, conductive materials are filled in the first

blind holes

141 and 142, respectively, so as to form first

conductive pillars

151 and 152. The first conductive pillar 151 is located in the first blind hole 141 and electrically contacts a portion of the first ground trace 132, and the first conductive pillar 152 is located in the first blind hole 152 and electrically contacts a portion of the first ground trace 136, a portion of the first power trace 137, and a portion of the first control trace 138, respectively.

Step S20, please refer to fig. 5-6, manufacturing at least one second circuit substrate 120 and at least one third circuit substrate 130, placing at least one second circuit substrate 120 on the first circuit substrate 110, placing at least one third circuit substrate 130 on at least one second circuit substrate 120, and pressing to obtain a circuit board stacked structure 140.

In this embodiment, the circuit board stacked structure 140 includes the first circuit board 110, two second circuit boards 120 respectively laminated on two opposite sides of the first circuit board 110, and two third circuit boards 130 respectively laminated on the second circuit boards 120.

In other embodiments, the circuit board stacked body 140 may further include one of the second circuit board 120 and the third circuit board 130 or more circuit boards.

The manufacturing method of the second circuit board 120 and the third circuit board 130 is the same as the manufacturing method of the first circuit board 110.

The second circuit board 120 includes a second base material layer 21 and a second conductive trace layer 23 formed on the second base material layer 21. The second conductive trace layer 23 includes at least two second ground traces 232 in the terminal region 101, and at least two second ground traces 236 and at least two second power traces 237 in the transmission line region 102. Wherein the

second ground lines

232 and 236 are located opposite to the

first ground lines

132 and 136 of the first conductive line layer 13. At least two second power supply lines 237 are opposed to the first conductive line layer 13 at the positions of the first power supply lines 137 within the transmission line region 102. At least two of the second power lines 237 are second transmission lines of the second circuit substrate 120. In other embodiments, the second transmission line may further include at least two second control lines.

In other embodiments, the second conductive trace layer 23 may further include at least two second control traces (not shown) located in the transmission line region 102.

At least two second blind holes 241 penetrating through the second substrate layer 21 and located in the terminal region 101, the second conductive pillars 152 filled in the second blind holes 142, at least four second blind holes 242 located in the transmission line region 102, and the second conductive pillars 252 filled in the second blind holes 242 are further formed on the second substrate layer 21. In the terminal region 101, a portion of the second ground line 232 is exposed from the second blind via 241 and electrically contacts the corresponding second conductive pillar 251. In the transmission line region 102, a portion of the second ground circuit 236 is exposed from the corresponding second blind via 242 and is electrically contacted with the corresponding second conductive pillar 252, and a portion of the second power circuit 237 is exposed from the corresponding second blind via 242 and is electrically contacted with the corresponding second conductive pillar 252.

In this embodiment, the second conductive trace layer 23 includes four second ground traces 232 located in the terminal region 101, six second ground traces 232 located in the transmission line region 102, and two second power traces 237 located in the transmission line region 102.

The third circuit board 130 includes a third base material layer 31 and a third conductive trace layer 33 formed on the third base material layer 31.

The third conductive trace layer 33 includes at least one third ground trace 332 in the terminal region 101, at least one third ground trace 336 in the transmission line region 102, at least two third power traces 337, and at least two third control traces 338. The third power trace 337 and the third control trace 338 are opposite to the first power trace 137 and the first control trace 138 of the first conductive trace layer 13, respectively. The third power supply line 337 and the third control line 338 are third transmission lines of the third circuit board 130. In other embodiments, the third transmission line may further include one of the third power line 337 and the third control line 338.

At least two third blind holes 341 penetrating through the third substrate layer 31 and located in the terminal region 101, a third conductive pillar 351 filled in the third blind holes 341, at least four third blind holes 342 located in the transmission line region 102, and the third conductive pillar 352 filled in the third blind holes 342 are further formed in the third substrate layer 31. In the terminal region 101, a portion of the third ground line 332 is exposed from the third blind via 341 and electrically contacts the corresponding third conductive pillar 351. In the transmission line region 102, a portion of the third ground circuit 336 is exposed from the corresponding third blind via 342 and electrically contacts the corresponding third conductive pillar 352, and a portion of the third power circuit 337 is exposed from the corresponding third blind via 342 and electrically contacts the corresponding third conductive pillar 352.

In this embodiment, the third conductive trace layer 33 further includes at least two third control traces 338, corresponding third blind holes 142 and corresponding third conductive pillars 152 located in the transmission line region 102, and the third control traces 338 are opposite to the first control traces 138 of the first conductive trace layer 13.

In this embodiment, the third conductive trace layer 33 includes one third ground trace 332 located in the terminal region 101, two third ground traces 332 located in the transmission line region 102, two third power traces 337 located in the transmission line region 102, and two third control traces 338 located in the transmission line region 102.

After the lamination, the second base material layer 21 of one of the second circuit substrates 120 is attached to the first conductive trace layer 13 of the first circuit substrate 110, and the second

conductive pillars

251 and 252 of the second circuit substrate 120 are electrically contacted with the first ground traces 132 and 136, the first power trace 137, and the first control trace 138 of the first circuit substrate 110, respectively; the first

conductive pillars

151 and 152 of the first circuit substrate 110 are in electrical contact with the

second ground lines

232 and 236 and the second power supply line 237, respectively, of the second conductive line layer 23 of the other second circuit substrate 120. In this embodiment, the first conductive pillars 152 of the second circuit substrate 120 and the first circuit substrate 110, which are located in the transmission line region 102 and correspond to the first control lines 138, are electrically contacted to the second conductive pillars 252. The third

conductive pillars

351 and 352 of one third circuit substrate 130 are electrically contacted to the

second ground lines

232 and 236 and the second control line 238 of the second electrically conductive line layer 23 of the second circuit substrate 120 on the same side, respectively. In this embodiment, the third conductive pillar 352 corresponding to the third control line 338 is in electrical contact with the corresponding second conductive pillar 252 of the second circuit substrate 120. The third

conductive pillars

151 and 152 of the other third circuit substrate 130 are respectively in electrical contact with the second

conductive pillars

251 and 252 of the second circuit substrate 120 on the same side.

Step S30, referring to fig. 7, at least one protective layer 150 is formed on at least one third circuit substrate 130, at least one opening 1501 is formed on the protective layer 150, and a portion of the third ground line 336 located in the transmission line region 102 is exposed from the opening 1501.

The protective layer 150 may be a cover film, a solder mask layer, or the like. Wherein, the solder mask layer can be green paint or ink, etc. In this embodiment, the protective layer 150 is a cover film.

In step S40, referring to fig. 8, a gold layer 160 is formed on the third grounding line 336 exposed from the opening 1501.

The gold plating layer 160 is used to protect the third grounding line 336 exposed from the opening 1501 from being oxidized or damaged.

Step S50, referring to fig. 9, at least one electromagnetic shielding layer 170 is formed on the protective layer 150 to obtain the high-frequency transmission circuit board 100, and a portion of the electromagnetic shielding layer 170 is electrically connected to the gold plating layer 160.

In this embodiment, the electromagnetic shielding layer 170 may also cover the side of the high-frequency transmission circuit board 100 in the transmission line region 102.

Referring to fig. 10, the high frequency transmission circuit board 100 further includes a bending region 103 connecting the transmission line region 102 and the terminal region 101.

Referring to fig. 4-5, 9 and 11, the internal structure of the high frequency transmission circuit board 100 of the terminal area 101 in the internal structure area of the high frequency transmission circuit board 100 located in the bending area 103 is substantially the same, and the difference is only that: the high-frequency transmission circuit board 100 located in the bending region 103 only includes the first substrate layer 11, the second substrate layer 21, the third substrate layer 31, the first conductive circuit layer 13, the second conductive circuit layer 23, and the third conductive circuit layer 33, but does not include the first

conductive pillars

151 and 152, the second

conductive pillars

251 and 252, and the third conductive pillars 351 and 352 (see fig. 5).

Referring to fig. 4-5 and 9-11, a high frequency transmission circuit board 100 according to a preferred embodiment of the invention is also provided. The high frequency transmission circuit board 100 is divided into two terminal areas 101 and a transmission line area 102 located between the two terminal areas 101. In the present embodiment, the high frequency transmission circuit board 100 includes a first circuit substrate 110, at least one second circuit substrate 120 formed on the first circuit substrate 110, and at least one third circuit substrate 130 formed on the second circuit substrate 120. In other embodiments, the high frequency transmission circuit board 100 may not include the third circuit substrate 130.

In this embodiment, the high frequency transmission circuit board 100 includes the first circuit substrate 110, two second circuit substrates 120 respectively formed on two opposite surfaces of the first circuit substrate 110, and two third circuit substrates 130 respectively formed on the second circuit substrates 120. In other embodiments, the high frequency transmission circuit board 100 may further include more circuit substrates.

The first conductive circuit layer 13 includes at least two

signal lines

131 and 135, at least four

first ground lines

132 and 136, at least four

first power lines

133 and 137, and at least four

first control lines

adjacent signal lines

131 or 135. The

first power lines

133 and 137 are used for connecting a power source (not shown). The

first control lines

134 and 138 are used to connect an antenna module (not shown).

At least two first blind holes 141 penetrating through the first substrate layer 11 and located in the terminal region 101, a first conductive pillar 151 filled in the first blind holes 141, at least six first blind holes 142 located in the transmission line region 102, and the first conductive pillar 152 filled in the first blind holes 142 are further formed in the first substrate layer 11. In the terminal region 101, a portion of the first ground line 132 is exposed from the first blind via 141 and electrically contacts the corresponding first conductive pillar 151. In the transmission line region 102, a portion of the first ground line 136 is exposed from the corresponding first blind via 142 and electrically contacts the corresponding first conductive pillar 152, and a portion of the first power supply line 137 and a portion of the first control line 138 are exposed from the corresponding first blind via 142 and electrically contacts the corresponding first conductive pillar 152.

The second circuit board 120 includes a second substrate layer 21 and a second conductive trace layer 23 formed on the second substrate layer 21. The second conductive trace layer 23 includes at least two second ground traces 232 in the terminal region 101, and at least two second ground traces 236 and at least two second power traces 237 in the transmission line region 102. Wherein the

second ground lines

232 and 236 are located opposite to the

first ground lines

132 and 136 of the first conductive line layer 13. At least two second power supply lines 237 are opposed to the first power supply line 137 of the first conductive line layer 13 in the transmission line region 102.

At least two second blind holes 241 penetrating through the second substrate layer 21 and located in the terminal region 101, the second conductive pillars 152 filled in the second blind holes 142, at least four second blind holes 242 located in the transmission line region 102, and the second conductive pillars 252 filled in the second blind holes 242 are further formed in the second substrate layer 21. In the terminal region 101, a portion of the second ground line 232 is exposed from the second blind via 241 and electrically contacts the corresponding second conductive pillar 251. In the transmission line region 102, a portion of the second ground circuit 236 is exposed from the corresponding second blind via 242 and is electrically contacted with the corresponding second conductive pillar 252, and a portion of the second power circuit 237 is exposed from the corresponding second blind via 242 and is electrically contacted with the corresponding second conductive pillar 252.

In the present embodiment, the second conductive trace layer 23 includes four second ground traces 232 located in the terminal region 101, six second ground traces 232 located in the transmission line region 102, and two second power traces 237 located in the transmission line region 102.

The third conductive trace layer 33 includes at least one third ground trace 332 located in the terminal region 101, at least one third ground trace 336 located in the transmission line region 102, at least two third power traces 337, and at least two third control traces 338. The third power trace 337 and the third control trace 338 are opposite to the first power trace 137 and the first control trace 138 of the first conductive trace layer 13, respectively.

In this embodiment, the third conductive trace layer 33 further includes at least two third control traces 338, corresponding third blind holes 342 and corresponding third conductive pillars 352 located in the transmission line region 102, and the third control traces 338 are opposite to the first control traces 138 of the first conductive trace layer 13.

In this embodiment, the third conductive trace layer 33 includes one third ground trace 332 in the terminal region 101, two third ground traces 332 in the transmission line region 102, two third power traces 337 in the transmission line region 102, and two third control traces 338 in the transmission line region 102.

The second base material layer 21 of one of the second circuit substrates 120 is attached to the first conductive circuit layer 13 of the first circuit substrate 110, and the second

conductive pillars

251 and 252 of the second circuit substrate 120 are electrically contacted to the

first ground lines

132 and 136, the first power line 137, and the first control line 138 of the first circuit substrate 110, respectively; the first

conductive pillars

second ground lines

conductive pillars

second ground lines

232 and 236 and the second control line 237 of the second electrically conductive line layer 23 of the second circuit substrate 120 on the same side, respectively. In this embodiment, the third conductive pillar 352 corresponding to the third control line 338 is in electrical contact with the corresponding second conductive pillar 252 of the second circuit substrate 120. The third

conductive pillars

351 and 352 of the other third circuit substrate 130 are in electrical contact with the second

conductive pillars

251 and 252 of the second circuit substrate 120 on the same side, respectively.

The first power circuit 137, the second power circuit 237, and the third power circuit 337 are connected in parallel by conductive pillars (152, 252, 253), and the first control circuit 138 and the third control circuit 338 are connected in parallel by conductive pillars (152, 252, 253).

The first power line 137, the second power line 237, and the third power line 337 may be collectively referred to as power lines of the high frequency transmission circuit board 100, the first control line 138 and the third control line 338 may be collectively referred to as control lines of the high frequency transmission circuit board 100, and both the power lines and the control lines may be transmission lines of the high frequency transmission circuit board 100. That is, the first transmission line, the second transmission line, and the third transmission line of the high frequency transmission circuit board 100, which are located in different circuit substrates, are stacked together and connected in parallel through the conductive pillar, so that the occupied space of the transmission line of the high frequency transmission circuit board 100 can be reduced.

The high frequency transmission circuit board 100 further includes at least one shielding layer 150 formed on the third circuit substrate 130 and an electromagnetic shielding layer 170 formed on the shielding layer 150 in the transmission line region 102.

At least one opening 1501 is formed in the protective layer 150, and part of the third ground line 336 in the transmission line region 102 is exposed from the opening 1501.

Part of the electromagnetic shielding layer 170 is electrically connected to the gold-plated layer 160.

Referring to fig. 4 to 5, 9 and 11, the internal structure of the high frequency transmission circuit board 100 in the terminal area 101 of the internal structure area of the high frequency transmission circuit board 100 located in the bending area 103 is substantially the same, and the difference is that: the high-frequency transmission circuit board 100 located in the bending region 103 only includes the first substrate layer 11, the second substrate layer 21, the third substrate layer 31, the first conductive circuit layer 13, the second conductive circuit layer 23, and the third conductive circuit layer 33, but does not include the first

conductive pillars

151 and 152, the second

conductive pillars

251 and 252, and the third conductive pillars 351 and 352 (see fig. 5).

The high-frequency transmission circuit board 100 provided by the invention comprises at least two circuit substrates, each circuit substrate positioned in a transmission line area comprises at least two transmission lines, the transmission lines positioned in different circuit substrates of the high-frequency transmission circuit board 100 are overlapped together and are connected in parallel through the conductive columns, so that the occupied space of the transmission lines of the high-frequency transmission circuit board 100 can be reduced; 2) The transmission lines positioned in different circuit substrates are overlapped together and are connected in parallel through the conductive columns, so that the resistance of the transmission lines can be reduced, and the loss can be reduced; 3) An electromagnetic shield layer 170 is formed on the periphery of the transmission line region 102 of the high frequency transmission circuit board 100, so as to prevent electromagnetic interference between the terminal region 101 and the bending region 103 of the high frequency transmission circuit board 100 and the transmission line region 102.

Although the present invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present invention.

Claims

1. A high-frequency transmission circuit board comprising a terminal area, a transmission line area, and a bent area connecting the terminal area and the transmission line area, the terminal area having a width equal to a width of the bent area, and the terminal area having a width greater than the width of the transmission line area, the high-frequency transmission circuit comprising:

a first circuit substrate; the first circuit substrate comprises a first substrate layer and a first conductive circuit layer formed on the first substrate layer, and the first conductive circuit layer is arranged in the terminal area, the transmission line area and the bending area; in the terminal area and the transmission line area, at least two first blind holes penetrating through the first base material layer are formed in the first base material layer from one side far away from the first conductive circuit layer, and first conductive columns are formed in the first blind holes; in the transmission line region, the first conductive circuit layer includes at least two first transmission lines exposed from the first blind holes and electrically contacted with the first conductive pillars; the first transmission line comprises at least one of a first power supply line and a first control line; in the terminal area, the first conductive circuit layer is exposed out of the first blind hole and is electrically connected with the first conductive pillar; in the bending area, the first blind hole is not formed in the first base material layer; and

at least one second circuit substrate formed on the first circuit substrate, wherein the second circuit substrate comprises a second base material layer and a second conductive circuit layer formed on the second base material layer, and the second conductive circuit layer is arranged in the terminal area, the transmission line area and the bending area; within the terminal area and the transmission line area; in the terminal area and the transmission line area, at least two second blind holes penetrating through the second base material layer are formed in the second base material layer from one side far away from the second conductive circuit, and second conductive columns are formed in the second blind holes; in the transmission line region, the second conductive circuit layer includes at least two second transmission lines exposed from the second blind via and electrically contacted to the second conductive pillars; the second transmission line comprises at least one of a second power supply line and a second control line; in the terminal area, the second conductive circuit layer is exposed out of the second blind hole and is electrically connected with the second conductive pillar; in the bending area, the second base material layer is not provided with the first blind hole; the first transmission lines and the corresponding second transmission lines are stacked together and connected in parallel through the first conductive columns or the second conductive columns.

2. The high-frequency transmission circuit board according to claim 1, further comprising at least one electromagnetic shield layer formed on an outermost side of the high-frequency transmission circuit board, the electromagnetic shield layer being electrically connected to a transmission line of a circuit substrate of the high-frequency transmission circuit board.

3. The high-frequency transmission circuit board according to claim 2, wherein the electromagnetic shield layer covers a side of the transmission line region of the high-frequency transmission circuit board.

4. The high-frequency transmission circuit board according to claim 3, further comprising a third circuit board formed on the second circuit board, the third circuit board including a third base material layer and a third conductive wiring layer formed on the third base material layer, the third conductive wiring layer being provided in the terminal region, the transmission line region and the bend region; in the terminal area and the transmission line area, at least two third blind holes penetrating through the third base material layer are formed in the third base material layer from one side far away from the third conductive circuit layer, and third conductive columns are formed in the third blind holes; the third conductive circuit layer comprises at least two third transmission lines, and the third transmission lines are positioned in the transmission line area; the third transmission line and the second transmission line that corresponds are established together and are passed through the third is led electrical pillar or the second is led electrical pillar with the third is led electrical pillar and is connected in parallel the bending region, not set up on the third substrate layer the third blind hole.

5. The high-frequency transmission circuit board according to claim 4, wherein the first circuit substrate further includes a signal line and a first ground line on one side of the signal line; the second circuit substrate further comprises a second ground line; the third circuit substrate further includes a third ground line; the first ground line, the second ground line, and the third ground line are electrically connected to each other through the first conductive pillar, the second conductive pillar, and the third conductive pillar, excluding the first conductive pillar, the second conductive pillar, and the third conductive pillar that electrically connect the first transmission line, the second transmission line, and the third transmission line; the signal line is separated from the first transmission line, the second transmission line and the third transmission line through the first grounding line, the second grounding line and the third grounding line.

6. The high-frequency transmission circuit board according to claim 5, wherein the signal line and the electromagnetic shield layer on the side edge or the first transmission line and the electromagnetic shield layer on the side edge are spaced apart by the conductive post.

7. The high-frequency transmission circuit board according to claim 5, wherein the signal line is located on the electromagnetic shielding layer side on the side edge, and the first transmission line is located on the electromagnetic shielding layer side on the side edge.

8. A method of manufacturing a high-frequency transmission circuit board including a terminal region, a transmission line region, and a bent region connecting the terminal region and the transmission line region, the terminal region having a width equal to a width of the bent region, and the terminal region having a width greater than a width of the transmission line region, comprising the steps of:

providing a first copper-clad substrate, wherein the first copper-clad substrate comprises a first base material layer and a first copper foil layer formed on the first base material layer;

manufacturing the first copper foil layer to form a first conductive circuit layer, wherein the first conductive circuit layer is arranged in the terminal area, the transmission line area and the bending area; in the transmission line region, the first conductive circuit layer includes at least two first transmission lines;

in the terminal area and the transmission line area, at least two first blind holes penetrating through the first base material layer are formed on one side of the first base material layer, which is far away from the first conductive circuit layer, and in the bending area, the first base material layer is not provided with the first blind holes; in the transmission line region, part of the first transmission line is exposed from the first blind hole, and in the terminal region, part of the first conductive circuit layer is exposed from the first blind hole; and

filling a conductive material in the terminal area and the first blind hole of the transmission line area respectively to form a first conductive pillar, wherein one end of the first conductive pillar is electrically contacted with a first transmission line exposed from the first blind hole in the transmission line area, and one end of the first conductive pillar is electrically contacted with the first conductive line layer exposed from the first blind hole in the terminal area;

providing a second copper-clad substrate, wherein the second copper-clad substrate comprises a second base material layer and a second copper foil layer formed on the second base material layer;

manufacturing the second copper foil layer to form a second conductive circuit layer, wherein the second conductive circuit layer is arranged in the terminal area, the transmission line area and the bending area; in the transmission line region, the second conductive line layer comprises at least two second transmission lines;

in the terminal area and the transmission line area, at least two second blind holes penetrating through the first base material layer are formed on one side, away from the second conductive circuit layer, of the second base material layer, and the second blind holes are not formed in the second base material layer in the bending area; in the transmission line region, a part of the second transmission line is exposed from the second blind hole, and in the terminal region, a part of the second conductive circuit layer is exposed from the second blind hole; and

filling a conductive material in the terminal area and the second blind hole of the transmission line area respectively to form a second conductive pillar, wherein one end of the second conductive pillar is electrically contacted with the first transmission line exposed from the first blind hole in the transmission line area, and one end of the second conductive pillar is electrically contacted with the second conductive line layer exposed from the second blind hole in the terminal area;

the first transmission lines and the corresponding second transmission lines are overlapped together and connected in parallel through the first conductive columns and the second conductive columns.

9. The method for manufacturing a high-frequency transmission circuit board according to claim 8, further comprising, after the step of press-fitting the second circuit substrate on the first circuit substrate, the steps of:

and at least one electromagnetic shielding layer is formed on the outermost side of the high-frequency transmission circuit board, and the electromagnetic shielding layer is electrically connected with the transmission line of the circuit substrate on the outermost side of the high-frequency transmission circuit board.