CN108617111A - A kind of manufacture craft of super thick copper circuit board - Google Patents
A kind of manufacture craft of super thick copper circuit board Download PDFInfo
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- CN108617111A CN108617111A CN201810413899.8A CN201810413899A CN108617111A CN 108617111 A CN108617111 A CN 108617111A CN 201810413899 A CN201810413899 A CN 201810413899A CN 108617111 A CN108617111 A CN 108617111A
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- Prior art keywords
- plate
- layer
- prepreg
- multilayer
- circuit board
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Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/46—Manufacturing multilayer circuits
- H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
- H05K3/4626—Manufacturing multilayer circuits by laminating two or more circuit boards characterised by the insulating layers or materials
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Production Of Multi-Layered Print Wiring Board (AREA)
Abstract
The present invention relates to wiring board production technical field, specially a kind of manufacture craft of super thick copper circuit board.The present invention is by optimizing pre- stack structure, it the use of fiberglass type is 106 in pre- stack structure and prepreg that gel content is RC74, and it is made of three prepreg overlappings positioned at the layer of prepreg of this outer layer, it is made of four prepreg overlappings positioned at other layers of layer of prepreg, coordinate specific pressing parameter simultaneously, there is filler deficiency in avoidable interlayer, has the problem of gap, and reduce interlayer alignment deviation.By optimizing the specific production method of solder mask, the bad problem of solder mask can avoid.The yields for making super thick copper circuit board by the method for the invention reaches 93% or more, and yields significantly improves.The problem of production method in the hole by adjusting optimization aperture more than or equal to 6.35mm, avoidable hole wall resin is cracked or is recessed.
Description
Technical field
The present invention relates to wiring board production technical field more particularly to a kind of manufacture crafts of super thick copper circuit board.
Background technology
The production procedure of wiring board is generally as follows：Core material is cut into required ruler in sawing sheet process by design requirement
Very little → pad pasting on core material → is removed not by the film of photocuring using internal layer film aligning exposure → development to form internal layer
Figure → layers of copper of non-envelope covering is to form internal layer circuit on etching core material → takes off film → by each core material by certain
It puts in order to stack and be formed as one multi-layer board → according to borehole data drill flute hole → electroless copper plating by high-temperature laminating and makes hole
Metallization → electric plating of whole board makes layers of copper thickness in hole reach design requirement → make the outer-layer circuit be connected with internal layer on multilayer boards
→ silk-screen solder mask and pass through the exposed and developed making solder mask → surface treatment → molding of film aligning, inspection on multilayer boards
The rear processes such as survey.
Currently, the copper thickness of more wiring board is between 2-4OZ in industry, it is however generally that, copper thickness >=350 μm
The wiring board of (10OZ) is referred to as super thick copper circuit board, and such wiring board is mainly high current substrate, and main application fields are electricity
Source module (power module) and automotive electronics component.But the existing method for making super thick copper circuit board is difficult to meet 10OZ thickness copper wire
The quality requirements that road plate makes, in pressing filler deficiency occur there is the problem of gap, and interlayer alignment deviation is big, slice analysis
Shi Kongbi is there are resin crackle or recess, the problems such as solder mask is bad, seriously affects the quality of wiring board, it is good to make electrical measurement for the first time
Rate is only 5.7%.
Invention content
The present invention provides a kind of pass through and optimizes life for the low problem of the yields of existing method making super thick copper circuit board
Produce the manufacture craft that flow improves the super thick copper wire wiring board of yields.
To achieve the above object, the present invention uses following technical scheme.
A kind of manufacture craft of super thick copper circuit board, includes the following steps：
S1：Pressing structure is pressed with trigger squeeze, multilayer is formed and produces plate；The pressing structure includes three pre-
Steel plate is respectively set in the upper and lower of pre- stack structure, between adjacent two steel plate and between steel plate and the bottom plate of pressing machine in stack structure
It is provided with buffer layer；Preferably, buffer layer is brown paper.
The pre- stack structure refers to folding core material, outer copper foil/outer layer core plate and layer of prepreg by design requirement
Merge the multilayered structure being fixed together.
The layer of prepreg for being located at time outer layer in the pre- stack structure is made of three prepreg overlappings, is located at other layers
Layer of prepreg be made of four prepregs overlapping；And the fiberglass type of prepreg is 106, gel content is
RC74。
S2：It drills on multilayer production plate according to pre-designed borehole data.
S3：So that multilayer is produced the hole metallization on plate by heavy copper and electric plating of whole board technique, then produces plate in multilayer
Outer layer makes outer-layer circuit.
S4：Solder mask is made on multilayer production plate.
S5：Process is processed after being carried out to multilayer production plate, and circuit board finished product is made.
Preferably, in step S1, pressing state modulator when being pressed to pressing structure with trigger squeeze is as follows：Pressing is total
Shi Changwei 171min；Temperature change mode is holding 20min at 140 DEG C, is then warming up to 160 DEG C with 3 DEG C/min and keeps the temperature extremely
18min is taken, be then warming up to 195 DEG C with 2 DEG C/min and is kept the temperature to time-consuming 19min, 210 are warming up to followed by with 1 DEG C/min
DEG C and keep the temperature to time-consuming 70min, then with 2 DEG C/min be cooled to 195 DEG C and keep the temperature to time-consuming 23min, be then gradually cooled to
Pressing working procedure terminates；Pressure is that 10min is kept at 100PSI, then boosts to 200PSI simultaneously with 20PSI/min
Pressurize then boosts to 250PSI with 25PSI/min and pressurize is to time-consuming 18min, followed by with 22PSI/ to time-consuming 10min
Min boosts to 360PSI and pressurize to time-consuming 112min, then with 15PSI/min is depressurized to 200PSI and pressurize is to taking
21min。
Preferably, in step S2, hole of the aperture more than or equal to 6.35mm is made in a manner of gong hole on multilayer production plate,
And 3 apertures of the position subdrilling that need to make the hole be 2.2mm pilot hole.
Preferably, in step S3, it is 1.5ASD × 45min that electric plating of whole board, which uses direct current, current parameters,；Outer-layer circuit system
It is 1.6ASD × 90min, waveform 13 that graphic plating in work, which uses pulse current, current parameters,:1.
Preferably, in step S4, first one layer of solder mask of silk-screen in the outer-layer circuit that multilayer produces plate, then to multilayer
It produces plate whole plate and carries out ink for screen printing twice；Vacuumize process is carried out to multilayer production plate after each ink for screen printing and is stood
60min。
Preferably, in manufacture craft described above, multilayer production plate on make solder mask after, carry multilayer production plate and
It frames up during placement, buffer layer is set between each multilayer production plate.
In manufacture craft described above, when the copper layer thickness on core material is more than design requirement, on core material
Microetch process is first passed through before making internal layer circuit, and the layers of copper on core material is thinned to the thickness for meeting design requirement.
Compared with prior art, the beneficial effects of the invention are as follows：The present invention is made by optimizing pre- stack structure in pre- stack structure
The prepreg that with fiberglass type be 106 and gel content is RC74, and positioned at the layer of prepreg of this outer layer by three and half
Cured sheets overlapping is constituted, and is made of four prepreg overlappings positioned at other layers of layer of prepreg, while coordinating specific pressure
Parameter is closed, avoidable interlayer filler deficiency occurs, has the problem of gap, and reduce interlayer alignment deviation.By optimizing solder mask
Specific production method, can avoid the bad problem of solder mask.The yields of super thick copper circuit board is made by the method for the invention
Reach 93% or more, yields significantly improves.The production method in the hole by adjusting optimization aperture more than or equal to 6.35mm,
The problem of can avoid cracked hole wall resin or recess.During carrying multilayer production plate and framing up placement, each multilayer
Buffer layer is set between production plate, can the plate face that often occurs of management and control field fabrication wipe flower problem.
Description of the drawings
Fig. 1 is the schematic diagram of pre- stack structure in embodiment；
Fig. 2 is schematic diagram when pressing structure and pressing machine bottom board are stacked together in embodiment.
Specific implementation mode
In order to more fully understand the technology contents of the present invention, with reference to specific embodiment to technical scheme of the present invention
It is described further and illustrates.
Embodiment
A kind of manufacture craft of super thick copper circuit board is present embodiments provided, the super thick copper circuit board is eight laminates,
Its essential information is as shown in the table：
| Press plate thickness | 4.718±0.437mm |
| Plate | TU-768 |
| Maximum PTH bores nozzle | 6.35mm |
| Minimum PTH bores nozzle | 1.6mm |
| Minimum range of the hole to copper | 0.175mm |
| The aspect ratio in the hole that need to be electroplated | 3:1 |
| The copper layer thickness of core material | 10OZ(350μm) |
| Hole wall copper layer thickness | >25.4μm |
| The thickness of table copper | >172μm |
Manufacture craft includes the following steps：
(1), sawing sheet：Core material and outer layer core plate are outputed by jigsaw size.
(2), internal layer circuit is made：
Because the copper layer thickness of core material is 10OZ, and product design requires the circuit of 3-6 layers of (L3-L6) internal layer circuit
Copper thickness is 9OZ, therefore first passes through microetch process before making internal layer circuit on core material and the layers of copper on core material is thinned
To the thickness for meeting design requirement.The etching speed for controlling microetch section in production line is 1.2m/min.Then exist by the prior art
Through making internal layer circuit on microetch treated core material.
(3) it presses：
Core material, outer layer core plate and layer of prepreg are overlapped and are fixed together by design requirement by pre- stack structure
Multilayered structure.In other embodiments, it can also be needed to replace outer layer core plate with outer copper foil according to the different designs of product.
The layer of prepreg for being located at time outer layer in pre- stack structure is made of three prepreg overlappings, is located at the half of other layers
Solidification lamella is made of four prepreg overlappings；And the fiberglass type of prepreg is 106, gel content is RC74.This
The pre- stack structure of embodiment is as shown in Figure 1,1 and 7 be outer layer core plate in figure, 2 and 6 are the layer of prepreg for being located at time outer layer, 3 Hes
5 be core material, and 4 be the layer of prepreg (this non-outer layer) positioned at other layers.
Pressing structure, as shown in Fig. 2, including three pre- stack structures 41,42,43, above and below pre- stack structure 41,42,43
Side is respectively set steel plate 31,32,33,34,35,36, is provided between adjacent two steel plate and between steel plate and the bottom plate of pressing machine
Brown paper buffer layer 21,22,23,24.In figure 11 and 12 be pressing machine bottom plate.
Pressing structure is pressed with trigger squeeze, multilayer is formed and produces plate.
Pressing parameter when trigger squeeze is pressed is as follows：Pressing total duration is 171min；Temperature change mode is 140
DEG C keep 20min, then with 3 DEG C/min be warming up to 160 DEG C and keep the temperature to time-consuming 18min, be then warming up to 195 with 2 DEG C/min
DEG C and keep the temperature to time-consuming 19min, followed by being warming up to 210 DEG C with 1 DEG C/min and keep the temperature to time-consuming 70min, then with 2 DEG C/min
It is cooled to 195 DEG C and keeps the temperature to time-consuming 23min, be then gradually cooled to pressing working procedure and terminate；Pressure be
10min is kept under 100PSI, and 200PSI is then boosted to 20PSI/min and pressurize is to time-consuming 10min, then with 25PSI/
Min boosts to 250PSI and pressurize to time-consuming 18min, followed by boosting to 360PSI with 22PSI/min and pressurize is to taking
112min is then depressurized to 200PSI and pressurize to time-consuming 21min with 15PSI/min.
Pressing parameter table when trigger squeeze is pressed is presented below：
| Stage | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| T0 | 140 | 140 | 140 | 160 | 195 | 210 | 195 | 195 | 180 | 140 |
| vT | 0 | 0 | 3 | 2 | 1 | 2 | 0 | 1 | 5 | 0 |
| T1 | 140 | 140 | 160 | 195 | 210 | 195 | 195 | 180 | 140 | 140 |
| Po | 100 | 100 | 200 | 250 | 360 | 360 | 360 | 360 | 200 | 200 |
| vp | 0 | 20 | 25 | 22 | 0 | 0 | 0 | 15 | 0 | 0 |
| P1 | 100 | 200 | 250 | 360 | 360 | 360 | 360 | 200 | 200 | 200 |
| t | 10 | 10 | 18 | 19 | 70 | 8 | 15 | 10 | 10 | 1 |
In upper table, T0Expression stage initial temperature, DEG C；vTIndicate heating rate, DEG C/min；T1Stage final temperature, DEG C；
PoExpression stage initial pressure, PSI；vpIndicate pressure change rate, PSI/min；P1Expression stage final pressure, PSI；When t is indicated
Between, min.
(4) outer layer drills：It drills on multilayer production plate according to pre-designed borehole data, and multilayer produces plate
Hole of the upper aperture equal to 6.35mm is made in a manner of gong hole, and is 2.2mm in 3 apertures of the position subdrilling that need to make the hole
Pilot hole.(in other embodiments, if being designed with the hole more than or equal to 6.35mm, this some holes is with above-described gong
Hole mode makes.)
(5) outer layer drills：It is drilled on production plate (Multi-layer force fit plate) according to drilling data.
(6) heavy copper and electric plating of whole board：Heavy copper process processing and the processing of electric plating of whole board process are carried out successively to multilayer production plate,
Make the hole metallization on production plate.Wherein, it is 1.5ASD × 45min that electric plating of whole board, which uses direct current, current parameters,.
(7) outer-layer circuit：Successively multilayer production plate on carry out pad pasting, exposure, development, graphic plating, move back film, etching,
Tin is moved back, outer-layer circuit is made on multilayer production plate.Wherein, graphic plating use pulse current, current parameters be 1.6ASD ×
90min, waveform 13:1.
(8) silk-screen welding resistance：First (i.e. Line mask are kept off one layer of solder mask of silk-screen in the outer-layer circuit that multilayer produces plate
Point silk-screen), ink for screen printing twice then is carried out to multilayer production plate whole plate；Multilayer production plate is carried out after each ink for screen printing
Vacuumize process simultaneously stands 60min.
(9) surface treatment (heavy nickel gold)：It is minimum in the nickel gold of the copper face uniform deposition design requirement thickness of welding resistance windowing position
Nickel is 3 μm thick, and minimum gold is 0.05 μm thick.
(10) electric performance test：Flying probe machine check multilayer produces the electric property of plate, detection multilayer production plate
Electric property detects qualified multilayer production plate and enters next processing link.
1000 pieces of multilayers production plate in same batch is detected, qualification rate 93.3%.
(11) it is molded：According to the prior art and design requirement gong shape is pressed, external form tolerance+0.05mm is made with just recessed
Lose the wiring board of filling holes with resin.
(12)FQC：According to customs inspection standard and our company test stone, super thick copper circuit board appearance is checked, such as
Defective timely repairing ensures to provide excellent quality control for client.
(13)FQA：Appearance, measured hole copper thickness, thickness of dielectric layers, green oil thickness, internal layer copper thickness etc. are taken a sample test again.
(14) it packs：By customer requirement, packaging is sealed to super thick copper circuit board, and is allowed to dry drying prescription and humidity card；Go out
Goods.
It is each more during carrying multilayer production plate and the placement that frames up after step 8 silk-screen welding resistance in the present embodiment
The buffer layer of setting such as soft rubber cushion etc between layer production plate, can the plate face that often occurs of management and control field fabrication wipe flower problem.
To the super thick copper circuit board that the present embodiment method makes, the slice analysis carried out in the production process is shown, interlayer
Do not occur the problem of insufficient filler and gap, interlayer alignment deviation is small；Aperture is equal to the hole of 6.35mm on plate, and hole wall resin does not go out
The problem of existing crackle or recess.
It is described above only with embodiment come the technology contents that further illustrate the present invention, in order to which reader is easier to understand,
But embodiments of the present invention are not represented and are only limitted to this, any technology done according to the present invention extends or recreation, is sent out by this
Bright protection.
Claims (6)
1. a kind of manufacture craft of super thick copper circuit board, which is characterized in that include the following steps：
S1：Pressing structure is pressed with trigger squeeze, multilayer is formed and produces plate；The pressing structure includes three pre- folded knots
Steel plate is respectively set in the upper and lower of pre- stack structure in structure, is arranged between adjacent two steel plate and between steel plate and the bottom plate of pressing machine
There is buffer layer；
The pre- stack structure refers to overlapping core material, outer copper foil/outer layer core plate and layer of prepreg simultaneously by design requirement
The multilayered structure being fixed together；
The layer of prepreg for being located at time outer layer in the pre- stack structure is made of three prepreg overlappings, is located at the half of other layers
Solidification lamella is made of four prepreg overlappings；And the fiberglass type of prepreg is 106, gel content is RC74；
S2：It drills on multilayer production plate according to pre-designed borehole data；
S3：So that multilayer is produced the hole metallization on plate by heavy copper and electric plating of whole board technique, the outer layer of plate is then produced in multilayer
Make outer-layer circuit；
S4：Solder mask is made on multilayer production plate；
S5：Process is processed after being carried out to multilayer production plate, and circuit board finished product is made.
2. a kind of manufacture craft of super thick copper circuit board according to claim 1, it is characterised in that：In step S1, with pressure
Pressing state modulator when trigger presses pressing structure is as follows：Pressing total duration is 171min；Temperature change mode is
20min is kept at 140 DEG C, be then warming up to 160 DEG C with 3 DEG C/min and is kept the temperature to time-consuming 18min, is then heated up with 2 DEG C/min
It to 195 DEG C and keeps the temperature to time-consuming 19min, followed by being warming up to 210 DEG C with 1 DEG C/min and keep the temperature to time-consuming 70min, then with 2
DEG C/min be cooled to 195 DEG C and keep the temperature to time-consuming 23min, be then gradually cooled to pressing working procedure and terminate；Pressure is
10min is kept at 100PSI, and 200PSI is then boosted to 20PSI/min and pressurize is to time-consuming 10min, then with 25PSI/
Min boosts to 250PSI and pressurize to time-consuming 18min, followed by boosting to 360PSI with 22PSI/min and pressurize is to taking
112min is then depressurized to 200PSI and pressurize to time-consuming 21min with 15PSI/min.
3. a kind of manufacture craft of super thick copper circuit board according to claim 1, which is characterized in that described in step S1
Pre- stack structure fixes each layer using pin-lam techniques.
4. a kind of manufacture craft of super thick copper circuit board according to claim 1, which is characterized in that in step S2, multilayer
Hole of the aperture more than or equal to 6.35mm is made in a manner of gong hole on production plate, and in the position subdrilling 3 that need to make the hole
A aperture is the pilot hole of 2.2mm.
5. a kind of manufacture craft of super thick copper circuit board according to claim 1, which is characterized in that in step S3, full plate
It is 1.5ASD × 45min that plating, which uses direct current, current parameters,；Graphic plating during outer-layer circuit makes uses pulse current,
Current parameters are 1.6ASD × 90min, waveform 13:1.
6. a kind of manufacture craft of super thick copper circuit board according to claim 1, which is characterized in that in step S4, first exist
Multilayer produces one layer of solder mask of silk-screen in the outer-layer circuit of plate, then carries out ink for screen printing twice to multilayer production plate whole plate；
Vacuumize process is carried out to multilayer production plate after each ink for screen printing and stands 60min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810413899.8A CN108617111A (en) | 2018-05-03 | 2018-05-03 | A kind of manufacture craft of super thick copper circuit board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810413899.8A CN108617111A (en) | 2018-05-03 | 2018-05-03 | A kind of manufacture craft of super thick copper circuit board |
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| Publication Number | Publication Date |
|---|---|
| CN108617111A true CN108617111A (en) | 2018-10-02 |
Family
ID=63661938
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810413899.8A Pending CN108617111A (en) | 2018-05-03 | 2018-05-03 | A kind of manufacture craft of super thick copper circuit board |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110049639A (en) * | 2019-04-28 | 2019-07-23 | 珠海中京电子电路有限公司 | A kind of print circuit plates making method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63315233A (en) * | 1987-06-18 | 1988-12-22 | Hitachi Cable Ltd | Manufacture of polyolefin metallic laminated sheet |
| CN103945640A (en) * | 2014-05-13 | 2014-07-23 | 张伯平 | Anti-static circuit board and manufacturing method thereof |
| CN105636368A (en) * | 2016-03-18 | 2016-06-01 | 奥士康科技股份有限公司 | Control method for uniformly laminating multi-layered PCB |
-
2018
- 2018-05-03 CN CN201810413899.8A patent/CN108617111A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63315233A (en) * | 1987-06-18 | 1988-12-22 | Hitachi Cable Ltd | Manufacture of polyolefin metallic laminated sheet |
| CN103945640A (en) * | 2014-05-13 | 2014-07-23 | 张伯平 | Anti-static circuit board and manufacturing method thereof |
| CN105636368A (en) * | 2016-03-18 | 2016-06-01 | 奥士康科技股份有限公司 | Control method for uniformly laminating multi-layered PCB |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110049639A (en) * | 2019-04-28 | 2019-07-23 | 珠海中京电子电路有限公司 | A kind of print circuit plates making method |
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