Radio frequency circuit board and manufacturing method thereof

Abstract

The invention provides a radio frequency circuit board and a manufacturing method thereof. The radio frequency circuit board comprises a circuit substrate and a plurality of connectors arranged on the circuit substrate. The circuit substrate comprises a substrate and a signal layer. Each of the plurality of connectors includes a metal post and a metal ring surrounding and separated from the metal post. The metal ring comprises a plurality of metal ring parts, and every two adjacent metal ring parts are arranged at intervals. Therefore, the connector can have a small height, and the purposes of miniaturization and thinning of products can be achieved.

Description

Technical Field

[0001] The invention relates to a radio frequency circuit board and a manufacturing method thereof, in particular to a radio frequency circuit board with a connector and a manufacturing method thereof. Background Art

[0002] Today's consumer electronic products usually use radio frequency connectors (or RF terminals) to operate in a radio environment with a high frequency range. RF connectors can be used to connect to the main circuit board. However, as the size of consumer electronic products is miniaturized, the size of current RF connectors can no longer meet their development trend. Summary of the invention

[0003] One aspect of the present invention is to provide a radio frequency circuit board, which includes a plurality of connectors.

[0004] Another aspect of the present invention is to provide a method for manufacturing a radio frequency circuit board.

[0005] According to one aspect of the present invention, a radio frequency circuit board is provided. The radio frequency circuit board includes a circuit substrate and a plurality of connectors arranged on the circuit substrate. The circuit substrate includes a substrate and a signal layer. Each of the plurality of connectors includes a metal column and a metal ring surrounding the metal column and separated from the metal column. The metal ring includes a plurality of metal ring parts, and two adjacent metal ring parts are spaced apart.

[0006] According to an embodiment of the present invention, the height of the metal column is not greater than the height of the metal ring, and the height of the connector is not greater than 0.1 mm.

[0007] According to an embodiment of the present invention, the radio frequency circuit board further includes a plurality of connector docking plates, wherein one of the plurality of connector docking plates is connected to one of the plurality of connectors.

[0008] According to one embodiment of the present invention, the plurality of connector docking plates include a cylinder and a plurality of annular complementary parts surrounding the cylinder, wherein the cylinder is not in contact with the plurality of annular complementary parts, and each of the plurality of annular complementary parts is respectively connected between two adjacent ones of the plurality of metal ring components.

[0009] According to an embodiment of the present invention, the plurality of connector docking boards connect the plurality of connectors by welding, light-curing adhesive or metal bonding.

[0010] According to one embodiment of the present invention, the signal layer includes a circuit layer arranged on the upper surface of the substrate; a signal line layer arranged on the lower surface of the substrate; and a plurality of conductive columns, wherein the signal line layer utilizes the plurality of conductive columns to connect the metal layer.

[0011] According to an embodiment of the present invention, the circuit substrate has a bending portion, and the bending portion is located between the plurality of connectors.

[0012] According to another aspect of the present invention, a method for manufacturing a radio frequency circuit board is provided. The method includes providing a flexible substrate, wherein the flexible substrate includes a substrate, an upper metal layer and a lower metal layer; forming a plurality of first holes, wherein the plurality of first holes extend from the upper metal layer into the substrate; filling the plurality of first holes with conductive materials to form a plurality of conductive posts; forming a plurality of metal connecting posts on the upper metal layer, wherein the plurality of conductive posts are between the plurality of metal connecting posts; patterning the flexible substrate to form a signal layer; making the plurality of metal connecting posts into a plurality of connectors, wherein each of the plurality of connectors includes a metal post and a metal ring surrounding the metal post, wherein the metal ring includes a plurality of metal ring parts, and the metal post does not contact the plurality of metal ring parts; and setting an electromagnetic shielding layer on the flexible substrate and covering the signal layer.

[0013] According to one embodiment of the present invention, the step of patterning the flexible substrate includes patterning the upper metal layer to form a circuit layer; patterning the lower metal layer to form a signal line layer, wherein the signal line layer utilizes the plurality of conductive pillars to connect the circuit layer.

[0014] According to an embodiment of the present invention, the step of patterning the flexible substrate includes etching a portion of the upper metal layer to form a bending portion of the flexible substrate, wherein the bending portion is located between the plurality of connectors.

[0015] According to an embodiment of the present invention, after manufacturing the plurality of connectors, the method further includes forming a plurality of connector docking plates, wherein one of the plurality of connector docking plates is connected to one of the plurality of connectors.

[0016] According to one embodiment of the present invention, before filling the conductive material into the plurality of first holes, the method further includes forming a plurality of second holes, wherein the plurality of second holes extend from the lower metal layer into the substrate; and the step of filling the conductive material into the plurality of first holes includes filling the conductive material into the plurality of second holes to form a plurality of conductive blind holes, and the plurality of metal connecting posts are located above the plurality of conductive blind holes.

[0017] The radio frequency circuit board and the manufacturing method thereof of the present invention utilize a metal connector with a relatively small height to achieve the purpose of miniaturization and thinning of the product, and the metal connector and the flexible circuit board are processed and formed at the same time to reduce the process cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be better understood by reading the following detailed description in conjunction with the accompanying drawings. It should be noted that, as is standard practice in the industry, many features are not drawn to scale. In fact, for the sake of clarity of discussion, the dimensions of many features may be scaled arbitrarily.

[0019] Figure 1A A top view of a radio frequency circuit board according to some embodiments of the present invention is shown.

[0020] Figure 1B A cross-sectional view of a radio frequency circuit board according to some embodiments of the present invention is shown.

[0021] Figure 2A A top view of a connector according to some embodiments of the present invention is shown.

[0022] Figure 2B The top view of the connector docking plate according to some other embodiments of the present invention is shown.

[0023] Figure 2C A top view of a connector and a connector docking plate after being combined according to some other embodiments of the present invention is shown.

[0024] Figure 3A , Figure 4A , Figure 5A , Fig. 6A , Fig. 7A and Fig. 8A A top view of an intermediate stage of a manufacturing process of a radio frequency circuit board according to some embodiments of the present invention is shown.

[0025] Figure 3B , Figure 4B , Figure 5B , Figure 6B , Figure 7B and Figure 8B A cross-sectional view is shown at an intermediate stage of a manufacturing process of a radio frequency circuit board according to some embodiments of the present invention. DETAILED DESCRIPTION

[0026] The present invention provides many different embodiments or illustrations to implement different features of the invention. The specific illustrations of components and configurations described below are intended to simplify the present invention. These are of course only examples and are not intended to be limiting. For example, the description of a first feature formed on or above a second feature includes an embodiment in which the first feature and the second feature are in direct contact, and also includes an embodiment in which other features are formed between the first feature and the second feature, so that the first feature and the second feature are not in direct contact. In addition, the present invention repeats component symbols and / or letters in various specific examples. The purpose of this repetition is to simplify and clarify the description and does not indicate a relationship between the various discussed embodiments and / or configurations.

[0027] Furthermore, spatially relative terms, such as "beneath," "below," "lower," "above," "upper," etc., are intended to facilitate description of the relationship of parts or features illustrated in the drawings to other parts or features. Spatially relative terms encompass different orientations of the elements in use or operation in addition to the orientation depicted in the drawings. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may be interpreted so.

[0028] As used herein, "around", "about", "approximately" or "substantially" generally means within 20 percent, within 10 percent, or within 5 percent of the stated value or range.

[0029] The radio frequency antenna in existing consumer electronic products is usually connected to the mainboard using a radio frequency connector (RF connector) and a transmission line. The inner diameter of a general RF connector is about 2 mm to about 10 mm, and the height is about 4 mm to about 8 mm. However, as the size of consumer electronic products is miniaturized, the present invention provides a radio frequency circuit board and a manufacturing method thereof, which utilizes a metal connector with a smaller height to achieve the purpose of miniaturization and thinning of the product, and the metal connector and the flexible circuit board are processed and formed at the same time to reduce the process cost.

[0030] See also Figure 1A and Figure 1B , which illustrates a top view and a cross-sectional view of a radio frequency circuit board 100 according to some embodiments of the present invention, wherein Figure 1B For along Figure 1A The cross-sectional view is shown by the section line AA in FIG. The RF circuit board 100 includes a circuit substrate 110 and a connector 120. The circuit substrate 110 includes a substrate 101 and a signal layer 130. In some embodiments, the circuit substrate 110 further includes a plurality of shielding conductive pillars 140. Figure 1A As shown, the shielding conductive pillar 140 is located around the signal layer 130 and is not in contact with or electrically connected to the signal layer 130. In addition, the shielding conductive pillar 140 has an electromagnetic shielding function to shield the signal layer 130 from interference caused by external electromagnetic waves.

[0031] The connector 120 is disposed on the circuit substrate 110. In some embodiments, the connectors 120 are respectively disposed on the conductive blind vias 105 and electrically connected to the conductive blind vias 105, wherein the conductive blind vias 105 are configured to extend from the signal line layer 138 (or the lower surface of the circuit substrate 110) to the substrate 101. The signal layer 130 is located between the two connectors 120. It should be noted that Figure 1A and Figure 1B The number of connectors 120 shown is two, but the number can be adjusted according to application requirements, and the present invention is not limited thereto.

[0032] See also Figure 2A , which shows a top view of a connector 120 according to some embodiments of the present invention. In some embodiments, the connector 120 includes a metal, such as copper. The connector 120 includes a metal column 122 and a metal ring 124. The metal column 122 can serve as a transmission line. The metal ring 124 includes a metal ring component 124A, a metal ring component 124B, a metal ring component 124C, and a metal ring component 124D. The metal ring 124 surrounds the metal column 122, and the metal column 122 does not contact the metal ring 124 (i.e., does not contact any of the metal ring component 124A, the metal ring component 124B, the metal ring component 124C, and the metal ring component 124D). It should be understood that Figure 2A The metal ring 124 is shown to include four metal ring components, but the number of metal ring components can be adjusted according to application requirements, and the present invention is not limited thereto.

[0033] There is a spacing between adjacent metal ring components 124A, metal ring components 124B, metal ring components 124C and metal ring components 124D, and the spacing is not limited, and each spacing can be the same or different. In some embodiments, the height of the metal column 122 is not greater than the height of the metal ring 124. In some embodiments, the height of the connector 120 is not greater than 0.1 mm, so that the electronic product can be miniaturized and thinned. There is no special limitation on the diameter D1 of the metal column 122, and it is preferably one-third of the diameter D2 of the connector 120. There is no special limitation on the distance d between the metal column 122 and the metal ring 124, and it is preferably one-sixth of the diameter D2 of the connector 120.

[0034] In some embodiments, the RF circuit board 100 includes a connector docking plate 150 to dock with the connectors 120 respectively. Figure 2B , which illustrates a top view of a connector docking plate 150 according to some embodiments of the present invention, wherein Figure 2B Only the elements of the connector docking plate 150 used to connect the connector 120 are depicted. The connector docking plate 150 includes a cylinder 152 and a plurality of ring-shaped complementary pieces (including a ring-shaped complementary piece 154A, a ring-shaped complementary piece 154B, a ring-shaped complementary piece 154C, and a ring-shaped complementary piece 154D).

[0035] See also Figure 2C , which shows a top view of the connector 120 and the connector docking plate 150 after being combined according to some embodiments of the present invention. The annular complementary parts 154A, the annular complementary parts 154B, the annular complementary parts 154C and the annular complementary parts 154D are respectively connected between two adjacent metal ring parts 124A, the metal ring parts 124B, the metal ring parts 124C and the metal ring parts 124D, and the cylinder 152 is connected to the metal column 122. After the connector 120 and the connector docking plate 150 are combined, the annular complementary parts 154A to the annular complementary parts 154D and the metal ring parts 124A to the metal ring parts 124D will surround the metal column 122 to form an electromagnetic shielding of the metal column 122.

[0036] Based on the above, in this embodiment, the metal ring 124 of the connector 120 is divided into multiple sections (including metal ring part 124A, metal ring part 124B, metal ring part 124C and metal ring part 124D), and combined with multiple sections of annular complementary parts (including annular complementary parts 154A, annular complementary parts 154B, annular complementary parts 154C and annular complementary parts 154D), which can increase the bonding strength of the product to prevent the consumer electronic product from being damaged due to bumping or falling during use. In addition, the connection between the connector 120 and the connector docking plate 150 can be made by welding (such as reflow soldering and electromagnetic welding), light curing adhesive or metal bonding, and can be combined with solder paste or conductive adhesive.

[0037] Please review Figure 1B , the signal layer 130 includes a circuit layer 132, a signal line layer 138 and a plurality of conductive pillars 135. In some embodiments, the circuit layer 132 is located on the upper surface 101A of the substrate 101, and the signal line layer 138 is located on the lower surface 101B of the substrate 101. The signal line layer 138 is electrically connected to the circuit layer 132 using the conductive pillars 135. In some embodiments, the signal line layer 138 and the circuit layer 132 are connected in parallel. In other embodiments, the circuit layer 132 can be directly disposed on the signal line layer 138; or the circuit layer 132 includes a circuit layer 132 that is simultaneously disposed on the signal line layer 138 and connected to the signal line layer 138 using the conductive pillars 135 (not shown). The configuration of the aforementioned signal layer 130 can reduce the loss of signal transmission, increase the ability to withstand high currents, and improve the quality and efficiency of signal transmission.

[0038] Please also see Figure 1A and Figure 1B, part of the circuit substrate 110 is exposed from the substrate 101 to serve as a bending portion 112. The bending portion 112 is a local area on the substrate 101 that does not have a metal layer (i.e., a local copper-etched area), which can increase the bending performance of the RF circuit board 100 and has static bending and dynamic bending capabilities, so it is beneficial for the application of the RF circuit board 100 in hinges, connecting plates, and folding screens to enhance the bending capability between connectors.

[0039] The following use Figure 3A , Figure 4A , Figure 5A , Fig. 6A , Fig. 7A and Fig. 8A and Figure 3B , Figure 4B , Figure 5B , Figure 6B , Figure 7B and Figure 8B The manufacturing process of the RF circuit board 100 is described. Figure 3A , Figure 4A , Figure 5A , Fig. 6A , Fig. 7A and Fig. 8A FIG. 1 is a top view of an intermediate stage of a manufacturing process of a radio frequency circuit board 100 according to some embodiments of the present invention. Figure 3B , Figure 4B , Figure 5B , Figure 6B , Figure 7B and Figure 8B A cross-sectional view of an intermediate stage of a manufacturing process of a radio frequency circuit board 100 according to some embodiments of the present invention is shown, wherein FIG. 3B to FIG. 8B The cross-sectional view is along Figure 1A The section line AA shown is drawn in section.

[0040] First, see Figure 3A and Figure 3B , providing a flexible substrate 201. The flexible substrate 201 includes a substrate 101, an upper metal layer 210A on an upper surface 101A of the substrate 101, and a lower metal layer 210B on a lower surface 101B of the substrate 101. In some embodiments, the substrate 101 includes but is not limited to polyimide (PI), polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP) or other suitable high-frequency materials. In some embodiments, the flexible substrate 201 is a flexible copper cladlaminate (FCCL).

[0041] See also Figure 4A and Figure 4B , forming a plurality of first holes 235, wherein the first holes 235 extend from the upper metal layer 210A into the substrate 101 but do not penetrate the lower metal layer 210B. The first holes 235 may be arranged in a row along the direction A1. Figure 4A , a plurality of grooves 240 may be formed on the upper and lower sides of the first hole 235, that is, the grooves 240 may be arranged in two rows along the direction A1. Figure 4B , a second hole 205 may be formed, wherein the second hole 205 extends from the lower metal layer 210B into the substrate 101 but does not penetrate the upper metal layer 210A. In some embodiments, the first hole 235 is located between two second holes 205 .

[0042] See also Figure 5A and Figure 5B , a metallization step is performed to fill the first hole 235 and the groove 240 with a conductive material to form a conductive column 135 and a shielding conductive column 140, respectively. At the same time, a conductive material is filled into the second hole 205 to form a conductive blind via 105. In some embodiments, the conductive material may be copper, tin or other suitable metal materials. In addition, a metal connection column 220 is formed on the upper metal layer 210A and above the conductive blind via 105.

[0043] See also Fig. 6A and Figure 6B , patterning the flexible substrate 201 to form a signal layer 130. The signal layer 130 includes a circuit layer 132, a signal line layer 138, and a plurality of conductive pillars 135. In some embodiments, the step of patterning the flexible substrate 201 includes patterning the upper metal layer 210A to form the circuit layer 132; and patterning the lower metal layer 210B to form the signal line layer 138. The circuit layer 132 and the signal line layer 138 can be electrically connected using the conductive pillars 135.

[0044] In some embodiments, a portion of the upper metal layer 210A may be removed to expose the substrate 101 and form a bending portion 112. The bending portion 112 is located between the metal connecting pillars 220. In some embodiments, the bending portion 112 is a local copper-etched area on the substrate 101. This design is beneficial for the application of the RF circuit board 100 in hinges, connecting plates, and folding screens to enhance the bending ability between connectors. Furthermore, the bending portion 112 contributes to the static bending and dynamic bending capabilities of the manufactured RF circuit board 100.

[0045] See also Fig. 7A and Figure 7B , the metal connecting column 220 (refer to Figure 5B ) is made into a connector 120. The connector 120 includes a metal column 122 and a metal ring 124. At the same time, the upper metal layer 210A is patterned (refer to Figure 5B ) between the metal connecting column 220 and the conductive blind hole 105 to form a pattern corresponding to the connector 120. So far, the manufacture of the RF circuit board 100 has been substantially completed.

[0046] In some embodiments, after forming the connector 120, the connector docking plate 150 (see Figure 2B ) to be connected to the connector 120 respectively. The connector 120 and the connector docking plate 150 can produce an electromagnetic shielding effect on the metal pillar 122 after being combined. The connection between the connector 120 and the connector docking plate 150 can be made by welding (such as reflow soldering and electromagnetic welding), light curing adhesive or metal bonding, and can be combined with solder paste or conductive adhesive.

[0047] See also Fig. 8A and Figure 8B , an electromagnetic shielding layer 250 is disposed above and below the flexible substrate 201 to cover the signal layer 130, the conductive blind via 105 and part of the substrate 101, but not the connector 120. In some embodiments, the height of the electromagnetic shielding layer 250 is about twice that of the signal line layer 138 to achieve complete signal shielding.

[0048] The present invention utilizes the above method to simultaneously manufacture the circuit board and the connector, thereby saving the cost of purchasing the existing RF connector and secondary installation, thereby reducing the production cost.

[0049] As described above, the present invention provides a radio frequency circuit board and a manufacturing method thereof, so as to utilize a connector with a relatively small height to achieve the purpose of miniaturization and thinness of the product, and simultaneously process and mold the connector and the flexible circuit board to reduce the process cost. Furthermore, the connector of the present invention is combined with the connector docking plate to achieve the effect of signal electromagnetic shielding for the transmission line in the middle of the connector.

[0050] Although the present invention has been disclosed as above with several embodiments, they are not intended to limit the present invention. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the definition of the attached claims.

[0051]

Explanation of symbols

[0052] 100: RF circuit board

[0053] 101:Substrate

[0054] 101A: Upper surface

[0055] 101B: Lower surface

[0056] 105: Conductive blind via

[0057] 110: Circuit board

[0058] 112: Bending part

[0059] 120: Connector

[0060] 122:Metal column

[0061] 124:Metal ring

[0062] 124A, 124B, 124C, 124D: Metal ring parts

[0063] 130:Signal layer

[0064] 132: Circuit layer

[0065] 135: Conductive column

[0066] 138:Signal circuit layer

[0067] 140: Shielding conductive column

[0068] 150: Connector docking plate

[0069] 152:Cylinder

[0070] 154A, 154B, 154C, 154D: Ring-shaped complementary parts

[0071] 201:Soft substrate

[0072] 205: Second hole

[0073] 210A: Upper metal layer

[0074] 210B: Lower metal layer

[0075] 220:Metal connecting column

[0076] 235: First hole

[0077] 240: Groove

[0078] 250:Electromagnetic shielding layer

[0079] A:Hatch Line

[0080] A1: Direction

[0081] D1,D2: diameter

[0082] d: distance.

Claims

1. A radio frequency circuit board, characterized in that: Include: A circuit substrate, comprising a substrate and a signal layer; and A plurality of connectors are disposed on the circuit substrate, wherein each of the plurality of connectors comprises: Metal columns; and The metal ring surrounds the metal column and is separated from the metal column, wherein the metal ring comprises a plurality of metal ring parts, and a distance is provided between two adjacent metal ring parts.

2. The radio frequency circuit board according to claim 1, characterized in that: The height of the metal column is not greater than the height of the metal ring, and the height of the connector is not greater than 0.1 mm.

3. The radio frequency circuit board according to claim 1, characterized in that: Also includes: A plurality of connector docking plates, wherein one of the plurality of connector docking plates is connected to one of the plurality of connectors.

4. The radio frequency circuit board according to claim 3, characterized in that: The plurality of connector docking plates include: cylinder; as well as A plurality of annular complementary parts surround the cylinder, wherein the cylinder is not in contact with the plurality of annular complementary parts, and each of the plurality of annular complementary parts is respectively connected between two adjacent ones of the plurality of metal ring components.

5. The radio frequency circuit board according to claim 3, characterized in that: The plurality of connectors are connected to the plurality of connectors by the connector docking board including welding, light curing adhesive or metal bonding.

6. The radio frequency circuit board according to claim 1, characterized in that: The signal layer comprises: A circuit layer is arranged on the upper surface of the substrate; A signal circuit layer is disposed on the lower surface of the substrate; and A plurality of conductive pillars, wherein the signal line layer is connected to the metal layer by using the plurality of conductive pillars.

7. The radio frequency circuit board according to claim 6, characterized in that: The circuit substrate has a bending portion, and the bending portion is located between the plurality of connectors.

8. A method for manufacturing a radio frequency circuit board, characterized in that: Include: Providing a flexible substrate, wherein the flexible substrate comprises a substrate, an upper metal layer and a lower metal layer; forming a plurality of first holes, wherein the plurality of first holes extend from the upper metal layer into the substrate; Filling the plurality of first holes with a conductive material to form a plurality of conductive pillars; forming a plurality of metal connecting posts on the upper metal layer, wherein the plurality of conductive posts are between the plurality of metal connecting posts; Patterning the flexible substrate to form a signal layer; The plurality of metal connecting columns are fabricated into a plurality of connectors, wherein each of the plurality of connectors comprises: Metal columns; as well as a metal ring surrounding the metal column, wherein the metal ring includes a plurality of metal ring parts, and the metal column does not contact the plurality of metal ring parts; and An electromagnetic shielding layer is arranged on the flexible substrate and covers the signal layer.

9. The method for manufacturing a radio frequency circuit board according to claim 8, characterized in that: The step of patterning the flexible substrate comprises: patterning the upper metal layer to form a circuit layer; The lower metal layer is patterned to form a signal circuit layer, wherein the signal circuit layer is connected to the circuit layer using the plurality of conductive pillars.

10. The method for manufacturing a radio frequency circuit board according to claim 8, characterized in that: The step of patterning the flexible substrate comprises: A portion of the upper metal layer is etched to form a bending portion of the flexible substrate, wherein the bending portion is located between the plurality of connectors.

11. The method for manufacturing a radio frequency circuit board according to claim 8, characterized in that: After manufacturing the plurality of connectors, the method further comprises: A plurality of connector docking plates are formed, wherein one of the plurality of connector docking plates is connected to one of the plurality of connectors.

12. The method for manufacturing a radio frequency circuit board according to claim 8, characterized in that: Before filling the conductive material into the plurality of first holes, the method further comprises: forming a plurality of second holes, wherein the plurality of second holes extend from the lower metal layer into the substrate; and The step of filling the conductive material into the plurality of first holes comprises: The conductive material is filled into the plurality of second holes to form a plurality of conductive blind vias, and the plurality of metal connecting pillars are located above the plurality of conductive blind vias.

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