A printed circuit board and its manufacturing method, and connector

Abstract

The present application discloses a printed circuit board and a manufacturing method thereof, and a connector. The printed circuit board includes a bottom substrate, a gold finger, a resist layer, a first resist layer and a top substrate; the gold finger includes a connected root and an end; the bottom surface of the resist layer covers the root and a part of the surface of the bottom substrate at the same time, and the end is exposed relative to the resist layer; the top surface of the resist layer includes a first part and a second part connected, wherein the first part is far away from the end, and the second part is close to the end; the first resist layer covers the first part and the second part is exposed relative to the first part. This structure can reduce the overflow of the gold finger root, ensure the surface size of the gold finger, and thus improve the electrical conductivity of the gold finger.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit boards, and in particular to a printed circuit board and a manufacturing method thereof, and a connector. Background Art

[0002] Gold fingers are golden conductive sheets arranged in rows on a circuit board, used to plug into the slot of another component and the electrical conductor of another component. Gold fingers are called gold fingers because their surface is gold-plated and the shape of the conductive sheets is similar to fingers. Gold fingers are generally made on the surface of a flat circuit board and close to the edge of the circuit board. The surface of ordinary gold fingers is flush; in order to meet some special market needs, some gold fingers are on the inner surface of the substrate, that is, the FR4 material outside the gold finger surface is mechanically removed to form a step. This type of printed circuit board is called a step gold finger printed circuit board.

[0003] Figure 1 It is a schematic diagram of the side view structure of an existing printed circuit board. Figure 2 for Figure 1 Please refer to the top view of the printed circuit board structure. Figure 1 and Figure 2 The step gold finger includes: a bottom substrate 101, a gold finger 102, a pure glue layer 103 and a top substrate 104, wherein the gold finger 102 is arranged on the surface of the substrate 101, the pure glue layer 103 is pressed on the specified position of the surface of the gold finger 102 and the substrate 101, and the top substrate 104 is pressed on top of the pure glue layer 103.

[0004] However, this structure will cause excessive glue overflow at the base of the gold finger during processing, affecting the size of the gold finger, resulting in glue overflow defects on the gold finger appearance and residual glue on the gold finger surface, affecting the electrical conductivity of the gold finger. Summary of the invention

[0005] The main technical problem solved by the present invention is to provide a printed circuit board and a manufacturing method thereof, and a connector, which can control the glue overflow at the root of the gold finger, ensure the surface size of the gold finger, and further improve the electrical conductivity of the gold finger.

[0006] In order to solve the above technical problems, a technical solution adopted by the present invention is: providing a printed circuit board, including: a bottom substrate, a gold finger, a resist layer, a first resist layer and a top substrate, the gold finger including a connected root and an end; the bottom surface of the resist layer covers the root and part of the surface of the bottom substrate at the same time, and the end is exposed relative to the resist layer; the top surface of the resist layer includes a first part and a second part connected, wherein the first part is far away from the end and the second part is close to the end; the first resist layer covers the first part, and the second part is exposed relative to the first resist layer.

[0007] The length of the second part in the first direction is greater than or equal to 0.3 mm, and the first direction is the direction from the first part to the second part.

[0008] The glue blocking layer includes a stacked glue blocking sub-layer and an adhesive sub-layer; the top surface of the glue blocking layer is arranged on the glue blocking sub-layer, and the bottom surface of the glue blocking layer is arranged on the adhesive sub-layer.

[0009] The material of the glue barrier layer is polyimide.

[0010] The first part of the glue-blocking layer is flush with one end of the first glue layer at one end away from the second part of the glue-blocking layer.

[0011] Part of the adhesive sublayer covers the surface of the root of the gold finger facing the top substrate, and the rest of the adhesive sublayer covers the surface of the bottom portion facing the top substrate.

[0012] Wherein, in the first direction, the length of the adhesive sublayer covering the root of the gold finger is greater than half of the length of the adhesive sublayer, and the length of the adhesive sublayer is greater than the length of the top substrate covering the first adhesive layer.

[0013] In order to solve the above technical problem, another technical solution adopted by the present invention is: to provide a connector, the connector comprises any one of the above-mentioned printed circuit boards.

[0014] In order to solve the above technical problems, another technical solution adopted by the present invention is: to provide a method for manufacturing a step gold finger printed circuit, including: providing a bottom substrate, a resist board, an adhesive material and a top substrate; wherein at least one gold finger is arranged on the top surface of the bottom substrate; the gold finger includes a connected root and an end, and the top surface of the resist board includes a connected first part and a second part, wherein the first part is far away from the end and the second part is close to the end; obtaining a combination; wherein the combination is obtained by stacking the bottom substrate, the resist board, the adhesive material and the top substrate in sequence; and in the combination, the bottom surface of the resist board covers the root and part of the surface of the bottom substrate at the same time, the end is exposed relative to the resist board, the adhesive material covers the first part, and the second part is exposed relative to the adhesive material; the combination is laminated to obtain a printed circuit board.

[0015] The resist material is stacked on the surface of the resist board, and the resist material fills the edge of the resist board; the resist board is pressed to the designated position of the gold finger and the bottom substrate.

[0016] The glue barrier plate comprises a laminated glue barrier sub-layer and an adhesive sub-layer.

[0017] The steps after pressing the adhesive blocking plate to the designated positions of the gold finger and the substrate include: stacking the adhesive material and the top substrate on the adhesive blocking plate in sequence.

[0018] The step of laminating the assembly includes: controlling the length of the second part in a first direction to be greater than or equal to 0.3 mm, wherein the first direction is the direction from the first part to the second part.

[0019] The steps after laminating the assembly include: surface coating the gold fingers with gold.

[0020] The beneficial effects of the present invention are as follows: Different from the prior art, the present invention is a bottom substrate, a gold finger, a resist layer, a first resist layer and a top substrate stacked in sequence; the gold finger includes a connected root and an end; the bottom surface of the resist layer covers the root and part of the surface of the bottom substrate at the same time, and the end is exposed relative to the resist layer; the top surface of the resist layer includes a connected first part and a second part, wherein the first part is far away from the end and the second part is close to the end; the first resist layer covers the first part, and the second part is exposed relative to the first resist layer. This structure can reduce the overflow of glue at the root of the gold finger, ensure the surface size of the gold finger, and thus improve the electrical conductivity of the gold finger. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0022] Figure 1 It is a schematic diagram of the side view structure of an existing printed circuit board;

[0023] Figure 2 yes Figure 1 A schematic diagram of the structure of a printed circuit board viewed from above;

[0024] Figure 3 It is a schematic diagram of a side view structure of a printed circuit board of the present invention;

[0025] Figure 4 yes Figure 3 A schematic diagram of a printed circuit board viewed from above;

[0026] Figure 5 The present invention is a schematic flow chart of a method for manufacturing a printed circuit board. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0028] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0029] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0030] See also Figure 3 and Figure 4 , Figure 3 It is a schematic diagram of a side view structure of a printed circuit board of the present invention. Figure 4 yes Figure 3 Schematic diagram of the top view structure of the printed circuit board. The printed circuit board 200 of this embodiment includes a bottom substrate 201, a gold finger 202, a resist layer 203, a first resist layer 204, and a top substrate 205. The gold finger 202 includes a connected root and an end, and the bottom surface of the resist layer 203 covers the root of the gold finger 202 and part of the surface of the bottom substrate at the same time, and the end of the gold finger 202 is exposed relative to the resist layer 203; the top surface of the resist layer 203 includes a first part and a second part connected, wherein the first part is far away from the end of the gold finger 202, and the second part is close to the end of the gold finger 202; the first resist layer 204 covers the first part of the resist layer 203, and the second part of the resist layer 203 is exposed relative to the first resist layer 204, and the bottom substrate 201, the resist layer 203, the first resist layer 204 and the top substrate 205 have the same width in the width direction of the step gold finger, wherein the width direction is Figure 4 The upper end of the printed circuit board points to the lower end.

[0031] In this embodiment, the length of the second portion of the rubber-blocking layer 203 in the first direction is greater than or equal to 0.3 mm, wherein the first direction is the direction from the first portion of the rubber-blocking layer 203 to the second portion.

[0032] In this embodiment, the gold fingers 202 are arranged in parallel on the inner layer of the bottom substrate 201, the spacing between the gold fingers 202 is equal, the outermost gold fingers 202 are at the same distance from the edge of the bottom substrate 201 in the direction of the step gold finger width, and the end of the gold finger 202 is away from the side of the root of the gold finger 202 close to the edge of the bottom substrate 201, and then the FR4 material outside the gold finger surface is removed by a mechanical method.

[0033] In this embodiment, the first part of the resist layer 203 is flush with one end of the first resist layer 204 at one end away from the second part of the resist layer 203, and the resist layer 203 is pressed on the gold finger 202 and the surface of the substrate 201 facing the top substrate 205. The resist layer 203 includes an adhesive sublayer 2031 and a resist sublayer 2032, the top surface of the resist layer 203 is arranged on the resist sublayer 2032, and the bottom surface of the resist layer 203 is arranged on the adhesive sublayer 2031, wherein the material of the resist sublayer 2032 is polyimide. Part of the adhesive sublayer 2031 is pressed onto the surface of the root of the gold finger 202 facing the top substrate 205, and the rest of the part is covered on the partial surface of the bottom substrate 201 facing the top substrate 205. In the first direction, the length of the adhesive sublayer 2031 covering the root of the gold finger 202 is greater than half of the length of the adhesive sublayer 2031, the length of the adhesive sublayer 2031 is greater than the length of the top substrate 205 covering the first adhesive layer 204, and the length of the adhesive resistance sublayer 2032 and the adhesive sublayer 2031 in the first direction is the same. When the adhesive resistance layer 203 is pressed onto the root of the gold finger 202 and part of the surface of the bottom substrate 201, an adhesive resistance material can be used, and the adhesive resistance layer can achieve glue overflow control below 0.1 mm to ensure that the surface area of ​​the gold finger 202 is qualified. The thickness of the adhesive resistance sublayer 2032 is less than the thickness of the adhesive sublayer 2031.

[0034] In this embodiment, the glue resistance layer 203 is pressed onto the root of the gold finger 202. During the pressing process, a glue resistance material is stacked on the surface of the glue resistance layer 203. The glue resistance material can use RP release film, etc., which is not limited here. After the glue resistance material fills all the edges of the glue resistance layer 203, the glue resistance layer 203 is pressed onto the surface of the gold finger 202 by a fast press. Among them, the edge of the glue resistance layer 203 is filled with glue resistance material, and the pure glue of the adhesive sublayer 2031 of the glue resistance layer 203 cannot enter the area filled with the glue resistance material, thereby achieving a glue resistance effect, realizing glue overflow control below 0.1mm, and ensuring that the surface area of ​​the gold finger is qualified.

[0035] In this embodiment, the first glue layer 204 is located between the top substrate 205 and the resist layer 203, and the first glue layer 204 is indented in the length direction of the gold finger 202 to the edge of the resist layer 203 and the top substrate 205, and the length of the portion of the first glue layer 204 not pressed with the resist layer 203 is less than the length of the portion of the top substrate 205 not pressed with the first glue layer 204, thereby ensuring that the overflow of the first glue layer 204 will not reach the edge of the resist layer 203. The first glue layer 204 pressed on the outer layer adopts an indented design, and the upper surface of the gold finger 202 at the indented position is protected by the resist layer 203, so there is no risk of infiltration and plating during the gold plating process. Among them, the first glue layer 204 can be pressed with pure glue, the thickness of the first glue layer 204 is less than the thickness of the resist layer 203, and the thickness of the resist layer 203 is less than the thickness of the top substrate 205.

[0036] In this embodiment, the top substrate 205 is pressed on the upper surface of the first adhesive layer 204, and the top substrate 205 and the bottom substrate 201 are both made of FR4 material, the gold finger 202 is made of copper material, and the surface of the gold finger 202 is gold-plated as a surface coating layer. The bottom substrate 201 is thinner than the top substrate 205.

[0037] In this embodiment, an end of the gold finger 202 away from the root of the gold finger 202 is close to the edge of the base substrate 201 , wherein the thickness of the gold finger 202 is less than the thickness of the base substrate 201 .

[0038] Different from the prior art, the present invention includes a bottom substrate, a gold finger, a resist layer, a first resist layer, and a top substrate; the gold finger includes a connected root and an end; the bottom surface of the resist layer covers the root and part of the surface of the bottom substrate at the same time, and the end is exposed relative to the resist layer; the top surface of the resist layer includes a first part and a second part connected, wherein the first part is far away from the end, and the second part is close to the end; the first resist layer covers the first part and the second part is exposed relative to the first part. This structure can reduce the overflow of glue at the root of the gold finger, ensure the surface size of the gold finger, and thereby improve the electrical conductivity of the gold finger.

[0039] Furthermore, different from the prior art, the present application also provides a connector, wherein the connector may include any of the above-mentioned printed circuit boards 200.

[0040] See also Figure 5 , Figure 5 This is a flow chart of a printed circuit board manufacturing method. Figure 5 As shown, the method comprises the following steps:

[0041] S501: Provide a bottom substrate, a resist, an adhesive material and a top substrate.

[0042] In this embodiment, at least one gold finger is arranged on the top surface of the bottom substrate, and the gold finger includes a connected root and an end. The top surface of the adhesive blocking plate includes a first part and a second part that are connected, wherein the first part is far away from the end of the gold finger, and the second part is close to the end of the gold finger; the first adhesive layer covers the first part, and the second part is exposed relative to the adhesive blocking material.

[0043] S502: Obtain the assembly.

[0044] In this embodiment, the assembly is obtained by stacking a bottom substrate, a glue blocking plate, an adhesive material and a top substrate in sequence; and in the assembly, the bottom surface of the glue blocking plate covers the root portion and a portion of the surface of the bottom substrate at the same time, the end portion is exposed relative to the glue blocking plate, the adhesive material covers the first portion, and the second portion is exposed relative to the adhesive material.

[0045] In this embodiment, the adhesive blocking material is stacked on the surface of the adhesive blocking board, and the adhesive blocking material fills the edge of the adhesive blocking board. Optionally, the adhesive blocking material can use RP release film, wherein the RP release film has a good filling and coating effect at a temperature of 185 degrees, and the temperature resistance can maintain performance within a short time of 190 degrees. Among them, the adhesive blocking board includes a stacked adhesive blocking sublayer and an adhesive sublayer, the adhesive blocking sublayer uses polyimide, and the adhesive sublayer uses epoxy series and acrylic series.

[0046] Specifically, the glue blocking material, glue blocking board, gold finger and bottom substrate are pressed together through the fast pressing machine pressing process. The temperature is maintained at 185 degrees during the pressing process for 2 minutes. During the pressing process, the RP release film fills the edge of the glue blocking board, and the glue of the glue blocking board cannot enter the area filled with the RP release film, thus achieving the effect of glue blocking and realizing glue overflow control.

[0047] After the glue blocking board is pressed onto the designated positions of the gold finger and the bottom substrate, the adhesive material and the top substrate are sequentially stacked on the glue blocking board, and the length of the second part of the glue blocking board in the length direction is controlled to be greater than or equal to 0.3 mm, wherein the first direction is the direction in which the first part of the glue blocking board points to the second part.

[0048] S503: Laminating the assembly.

[0049] In this embodiment, the adhesive material is pressed between the top substrate and the adhesive block plate, and the adhesive material is indented in the first direction to the adhesive block plate and the edge of the top substrate. The adhesive material adopts an indented design to ensure that the adhesive overflow of the adhesive material does not reach the edge of the adhesive block plate. The adhesive material pressed on the outer layer adopts an indented design, and the gold finger at the indented position is protected by the adhesive block plate on the surface facing the top substrate, so there is no risk of infiltration and plating during the gold plating process. Among them, the adhesive material can be pressed with pure glue, the thickness of the adhesive material is less than the thickness of the adhesive block plate, and the thickness of the adhesive block plate is less than the thickness of the top substrate.

[0050] Optionally, the first portion of the adhesive blocking plate is flush with one end of the adhesive material at an end away from the second portion of the adhesive blocking plate.

[0051] In this embodiment, the top substrate is pressed onto the surface of the adhesive material, and both the top substrate and the bottom substrate are made of FR4 material, and the gold fingers are made of copper material.

[0052] In this embodiment, after the bottom substrate, the adhesive plate, the adhesive material and the top substrate are pressed together through the outer layer pressing process, the ends of the gold fingers are subjected to surface gold plating as a surface coating layer, thereby obtaining gold fingers and a printed circuit board with step gold fingers. Among them, since the first adhesive layer of the outer layer pressing adopts an inward-retracted design, the surface of the gold finger at the inward-retracted position is protected by the adhesive layer, and there is no risk of infiltration and plating during the surface gold plating process, thereby avoiding the risk of short circuit.

[0053] Different from the prior art, the present invention provides a bottom substrate, a glue blocking plate, an adhesive material and a top substrate; wherein, at least one gold finger is arranged on the top surface of the bottom substrate; the gold finger includes a connected root and an end, and the top surface of the glue blocking plate includes a connected first part and a second part, wherein the first part is far away from the end and the second part is close to the end; the first glue layer covers the first part, and the second part is exposed relative to the first glue layer. Through the above method, the overflow of glue at the root of the gold finger can be reduced, the surface size of the gold finger can be guaranteed, and the risk of chemical gold plating can be reduced.

[0054] The above description is only an implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A printed circuit board, It is characterized in that The printed circuit board comprises a bottom substrate, a gold finger, a resist layer, a first adhesive layer and a top substrate which are stacked in sequence; The gold finger includes a connected root and an end; the bottom surface of the resist layer covers the root and a part of the surface of the bottom substrate at the same time, and the end is exposed relative to the resist layer; The top surface of the adhesive layer includes a first portion and a second portion connected, wherein the first portion is far away from the end portion, and the second portion is close to the end portion; the first adhesive layer covers the first portion, and the second portion is exposed relative to the first adhesive layer; The surface of the glue-blocking layer is provided with a glue-blocking material, and the glue-blocking material is filled at the edge of the glue-blocking layer; The first glue layer is located between the top substrate and the glue resistance layer, and the first glue layer is retracted inwardly to the glue resistance layer and the edge of the top substrate in the length direction of the gold finger, and the length of the portion of the first glue layer not laminated with the glue resistance layer is smaller than the length of the portion of the top substrate not laminated with the first glue layer.

2. The printed circuit board according to claim 1, It is characterized in that The length of the second portion in a first direction is greater than or equal to 0.3 mm, wherein the first direction is a direction from the first portion to the second portion.

3. The printed circuit board according to claim 2, It is characterized in that The glue-blocking layer comprises a stacked glue-blocking sub-layer and an adhesive sub-layer; the top surface of the glue-blocking layer is arranged on the glue-blocking sub-layer, and the bottom surface of the glue-blocking layer is arranged on the adhesive sub-layer.

4. The printed circuit board according to claim 3, It is characterized in that The material of the glue blocking layer is polyimide.

5. The printed circuit board according to claim 3, It is characterized in that The first portion of the adhesive resistance layer is flush with one end of the first adhesive layer at one end away from the second portion of the adhesive resistance layer.

6. The printed circuit board according to claim 3, It is characterized in that Part of the adhesive sublayer covers the surface of the root of the gold finger facing the top substrate, and the remaining part covers a part of the surface of the bottom substrate facing the top substrate.

7. The printed circuit board according to claim 6, It is characterized in that In the first direction, the length of the adhesive sublayer covering the root of the gold finger is greater than half of the length of the adhesive sublayer, and the length of the adhesive sublayer is greater than the length of the top substrate covering the first glue layer.

8. A connector, It is characterized in that A printed circuit board comprising any one of claims 1 to 7.

9. A method for manufacturing a printed circuit board, It is characterized in that The production method comprises: A bottom substrate, a resist plate, an adhesive material and a top substrate are provided; wherein at least one gold finger is arranged on the top surface of the bottom substrate; the gold finger comprises a connected root and an end, and the top surface of the resist plate comprises a connected first part and a second part, wherein the first part is far away from the end, and the second part is close to the end; Obtain a combination; wherein the combination is obtained by stacking the bottom substrate, the adhesive plate, the adhesive material and the top substrate in sequence; and in the combination, the bottom surface of the adhesive plate covers the root and part of the surface of the bottom substrate at the same time, the end is exposed relative to the adhesive plate, the adhesive material covers the first part, and the second part is exposed relative to the adhesive material; the adhesive material is stacked on the surface of the adhesive plate, and the adhesive material fills the edge of the adhesive plate; the adhesive plate is pressed to the designated position of the gold finger and the bottom substrate; laminating the assembly to obtain the printed circuit board; The adhesive material is located between the top substrate and the adhesive blocking plate, and the adhesive material is retracted inwardly to the adhesive blocking plate and the edge of the top substrate in the length direction of the gold finger, and the length of the portion of the adhesive material not pressed against the adhesive blocking plate is less than the length of the portion of the top substrate not pressed against the adhesive material.

10. The method according to claim 9, It is characterized in that The glue blocking plate comprises a stacked glue blocking sub-layer and an adhesive sub-layer.

11. The method according to claim 9, It is characterized in that The steps after pressing the adhesive blocking plate to the designated positions of the gold finger and the bottom substrate include: The adhesive material and the top substrate are sequentially stacked on the adhesive blocking plate.

12. The method according to claim 9, It is characterized in that The step of laminating the assembly comprises: The length of the second part in a first direction is controlled to be greater than or equal to 0.3 mm, wherein the first direction is a direction in which the first part points to the second part.

13. The method according to claim 9, It is characterized in that The steps after laminating the assembly include: The gold finger is subjected to surface gold plating.

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