CN111818735A

CN111818735A - Cavity plate resistance welding manufacturing method and circuit board

Info

Publication number: CN111818735A
Application number: CN202010528310.6A
Authority: CN
Inventors: 冯忠
Original assignee: Zhuhai Doumen Chaoyi Industry Co ltd
Current assignee: Zhuhai Doumen Chaoyi Industry Co ltd
Priority date: 2020-06-11
Filing date: 2020-06-11
Publication date: 2020-10-23

Abstract

The invention discloses a cavity plate resistance welding manufacturing method and a circuit board, wherein the method comprises the steps of transferring an inner layer pattern, and etching a preset circuit pattern on a circuit layer of a PCB inner layer plate; sticking a protective adhesive tape, namely sticking the protective adhesive tape on a preset cavity area and a target area; laminating, namely laminating and laminating the PCB inner layer plates pasted with the protective tapes according to a preset lamination sequence; transferring an outer layer pattern, laminating and laminating an inner layer board of the PCB to form the PCB with an outer layer circuit, and etching a preset circuit pattern on the outer layer circuit of the PCB; uncovering, namely uncovering the PCB pair subjected to outer layer pattern transfer to expose the cavity area and the target area; and solder mask spray printing, wherein solder mask ink is sprayed and printed in the cavity area through a solder mask spray printing machine. The inner layer is subjected to spray printing after the pressing procedure without high-temperature pressing, so that the quality problems of solder resistance falling, heterochrosis or cracking in the prior art can be avoided.

Description

Cavity plate resistance welding manufacturing method and circuit board

Technical Field

The invention relates to the technical field of circuit boards, in particular to a cavity board resistance welding manufacturing method and a circuit board.

Background

With the development of the PCB industry and the application of 2.5D technology, more and more circuit board products adopting cavity design are available. For a product with a cavity area printed with solder resist and mounted with components, the process flow generally comprises the following steps: inner layer pattern transfer, inner layer resistance welding, protective tape pasting, pressing, outer layer drilling, outer layer electroplating, outer layer pattern transfer and cover uncovering. The inner layer is printed with the solder resist, and then the ink is pressed at high temperature, so that the quality defects of solder resist falling, heterochromatic or cracking can be caused. After the outer layer is uncovered, the bottom of the cavity and the plate surface have height difference, and the requirements cannot be met by adopting the traditional silk-screen and exposure process.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a method for manufacturing the cavity plate by resistance welding, the inner layer resistance welding does not need high-temperature pressing, and the quality problem of the inner layer resistance welding in the prior art can be solved.

In a first aspect, a method for manufacturing a cavity plate by resistance welding according to an embodiment of the invention comprises the following steps:

transferring the inner layer pattern, and etching a preset circuit pattern on the circuit layer of the PCB inner layer board;

sticking a protective adhesive tape, namely sticking the protective adhesive tape on a preset cavity area and a target area;

laminating, namely laminating and laminating the PCB inner layer plates pasted with the protective tapes according to a preset lamination sequence;

transferring an outer layer pattern, laminating and laminating an inner layer board of the PCB to form the PCB with an outer layer circuit, and etching a preset circuit pattern on the outer layer circuit of the PCB;

uncovering, namely uncovering the PCB pair subjected to outer layer pattern transfer to expose the cavity area and the target area;

and solder mask spray printing, wherein solder mask ink is sprayed and printed in the cavity area through a solder mask spray printing machine.

According to some embodiments of the invention, the solder mask printing specifically comprises the following steps:

the method comprises the following steps of (1) constructing a circuit dam, and spraying and printing solder resist ink along the edge of a circuit pattern of the PCB inner layer plate to form edge solder resist of the circuit pattern;

and spraying printing surface oil, and spraying and printing solder resist ink on the outer surface of the PCB inner layer plate to form surface solder resist.

According to some embodiments of the invention, the line is dammed by jet printing solder resist ink a plurality of times such that the height of the edge solder resist is greater than the thickness of the surface solder resist.

According to some embodiments of the present invention, the solder resist jet printed PCB is baked for 2 hours at a baking temperature of 150 ± 5 ℃.

According to some embodiments of the invention, the uncovering comprises the following steps:

cutting the outer layer of the PCB by adopting carbon dioxide laser according to preset production data;

and (4) taking off the cut area by using an adhesive tape or tweezers.

According to some embodiments of the invention, the aperture of the carbon dioxide laser is 150 ± 10um, the laser hole folding knife amount is 50%, and the laser width is 0.75 ± 0.01 mm.

In a second aspect, the invention provides a circuit board, which is prepared by the above-mentioned cavity plate solder mask manufacturing method.

According to one or more technical schemes of the embodiment of the invention, the method has at least the following beneficial effects: the inner layer is subjected to spray printing after the pressing procedure without high-temperature pressing, so that the quality problems of solder resistance falling, heterochrosis or cracking in the prior art can be avoided.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a process flow diagram of a cavity plate resistance welding manufacturing method according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an inner layer board of a PCB subjected to inner layer pattern transfer according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of an inner layer board of a PCB to which a protective tape is attached according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a laminated PCB according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a PCB subjected to outer layer pattern transfer in an embodiment of the present invention;

FIG. 6 is a schematic diagram of a PCB with a cover removed according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a solder resist printed PCB according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of the layout of the printed area of the inner layer board of the PCB according to the embodiment of the invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to, for example, the inner and outer indications, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, but does not indicate or imply that the indicated device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.

In the description of the present invention, the meaning of plural times is two or more times, and greater than, less than, more than, etc. are understood as excluding the present numbers, and greater than, less than, etc. are understood as including the present numbers. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

Referring to fig. 1, the present embodiment discloses a method for manufacturing a cavity plate by solder mask, which includes the steps of transferring an inner layer pattern, attaching a protective tape, pressing, transferring an outer layer pattern, uncovering, and solder mask spray printing. Compared with the existing manufacturing method, the inner layer solder mask of the embodiment of the invention is subjected to spray printing after the pressing process, high-temperature pressing is not needed, and the quality problems of solder mask falling, heterochromous or cracking in the prior art can be avoided.

The above steps are described in detail below with reference to fig. 2 to 7:

inner layer pattern transfer: referring to fig. 2, after the processes of film pasting, exposure, development and etching are performed according to the production data of the PCB, a predetermined circuit pattern is etched on the circuit layer 120 of the inner layer board of the PCB, wherein the inner layer board 100 of the PCB includes a substrate layer 110 and the circuit layer 120 of the inner layer board.

Pasting a protective adhesive tape: referring to fig. 2 and 3, according to the production data, a protective tape 130 is attached to the preset cavity area 121 and the target area 122 so as to expose the cavity area 121 and the target area 122 by subsequent uncovering, wherein an alignment target is disposed in the target area 122 and is used for subsequent solder resist printing alignment.

And (3) laminating: referring to fig. 4, the inner PCB 100 with the protective tape 130 applied thereon is laminated according to a predetermined lamination sequence, and the laminated PCB includes the inner PCB 100, a prepreg 140 and an outer circuit 150, wherein the outer circuit 150 may be a copper foil or a copper clad laminate.

Transferring an outer layer pattern: referring to fig. 4 and 5, the inner layer board of the PCB is laminated to form a PCB having an outer layer circuit, and a predetermined circuit pattern is etched on the outer layer circuit 150 of the PCB;

uncovering: referring to fig. 5 and 6, the PCB pair subjected to the outer layer pattern transfer is uncovered to expose the cavity area 121 and the target area 122;

solder resist spray printing: referring to fig. 6 and 7, solder resist ink is sprayed in the cavity area 121 by a solder resist sprayer.

The solder mask spray printing specifically comprises the following steps:

building a dam for the line: referring to fig. 7 and 8, solder resist ink is sprayed along the edge of the circuit pattern of the PCB core board 100 to form an edge solder resist 210 of the circuit pattern;

spraying printing face oil: referring to fig. 7, solder resist ink is sprayed on the outer surface of the PCB core board 100 to form a surface solder resist 220, and referring to fig. 8, it is understood that the outer surface of the PCB core board 100 has a circuit pattern area and a non-circuit area 101, the circuit pattern area of the PCB core board 100 includes a pad area 102 and a non-pad area 103, wherein the outer surface of the pad area 102 does not need to be sprayed with solder resist ink, the outer surfaces of the non-circuit area 101 and the non-pad area 103 need to be sprayed with solder resist ink, and the surface solder resist 220 and the edge solder resist 210 cover the circuit pattern of the PCB core board 100, thereby forming solder resist protection.

Referring to fig. 7, to prevent the solder pads from being on the ink, the circuit is dammed by spraying the solder resist ink several times so that the height of edge solder resist 210 is greater than the thickness of surface solder resist 220. The number of times of spraying is 3 in the embodiment, so that the thickness of the edge solder mask 210 is larger than that of the surface solder mask 220, and when the surface oil is sprayed, the edge solder mask 210 sprayed and printed on the edge of the bonding pad 105 can block the solder mask ink splashed in the spraying and printing process, and the solder mask ink is prevented from being splashed on the bonding pad 105.

And after the solder mask spray printing is finished, baking the PCB subjected to the solder mask spray printing for 2 hours at the baking temperature of 150 +/-5 ℃ to finish the inner layer solder mask manufacturing.

In the above step, uncovering specifically comprises the steps of:

after the cutting is completed, the cut area is uncovered by using an adhesive tape or tweezers.

Wherein, the aperture of carbon dioxide laser is 150 +/-10 um, the laser hole folding cutter amount is 50%, and the laser width is 0.75 +/-0.01 mm.

The embodiment of the invention also provides a circuit board which is prepared by the cavity plate resistance welding manufacturing method. The inner layer solder mask of the embodiment of the invention is subjected to spray printing after the pressing procedure, high-temperature pressing is not needed, and the quality problems of solder mask falling, heterochromatic or cracking in the prior art can be avoided.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims

1. A cavity plate resistance welding manufacturing method is characterized by comprising the following steps:

2. The cavity plate solder mask manufacturing method of claim 1, wherein the solder mask jet printing specifically comprises the following steps:

3. A method for solder resist fabrication of a cavity plate as claimed in claim 2, wherein the wiring damming is performed by multiple times of spraying solder resist ink so that the height of the edge solder resist is greater than the thickness of the surface solder resist.

4. A method for solder resist fabrication of a cavity plate as claimed in any one of claims 1 to 3 wherein the solder resist printed PCB is baked for 2 hours at a baking temperature of 150 ± 5 ℃.

5. The cavity plate resistance welding manufacturing method according to claim 1, wherein the uncovering specifically comprises the following steps:

and (4) taking off the cut area by using an adhesive tape or tweezers.

6. The cavity plate resistance welding manufacturing method of claim 5, wherein the aperture of the carbon dioxide laser is 150 ± 10um, the laser aperture folding knife amount is 50%, and the laser width is 0.75 ± 0.01 mm.

7. A wiring board produced by the cavity plate solder resist production method as set forth in any one of claims 1 to 6.