CN109121300A - A kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate - Google Patents
A kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate Download PDFInfo
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- CN109121300A CN109121300A CN201811121354.6A CN201811121354A CN109121300A CN 109121300 A CN109121300 A CN 109121300A CN 201811121354 A CN201811121354 A CN 201811121354A CN 109121300 A CN109121300 A CN 109121300A
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- plate
- production
- stepped groove
- copper
- layer
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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
- H05K3/0011—Working of insulating substrates or insulating layers
- H05K3/0044—Mechanical working of the substrate, e.g. drilling or punching
-
- 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
- H05K3/10—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
- H05K3/18—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using precipitation techniques to apply the conductive material
-
- 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
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/02—Details related to mechanical or acoustic processing, e.g. drilling, punching, cutting, using ultrasound
- H05K2203/0228—Cutting, sawing, milling or shearing
-
- 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
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/10—Using electric, magnetic and electromagnetic fields; Using laser light
- H05K2203/107—Using laser light
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Structure Of Printed Boards (AREA)
Abstract
The invention discloses a kind of production methods of the accurate controlled depth milling slot of microwave printed circuit plate, comprising the following steps: forms stepped groove on production plate by way of controlled depth milling slot；And the slot bottom of the stepped groove is located on the inside of Rogers high frequency plate in the dielectric layer on layers of copper top；Heavy copper and electric plating of whole board processing are carried out to production plate, the slot bottom of stepped groove and cell wall is made to plate one layer of layers of copper；The pad pasting on production plate then forms outer-layer circuit figure on production plate by exposing, being developed in, then carries out graphic plating to production plate；Gong removes the electroplated layer of stepped groove slot bottom, exposes the dielectric layer of slot bottom；The dielectric layer of stepped groove slot bottom is burnt up by laser, exposes the layers of copper on the inside of Rogers high frequency plate；Production plate is carried out except the layers of copper for after glue processing, passing through exposing at alkali etching removing stepped groove slot bottom.The method of the present invention realizes zero damage of Rogers high frequency plate, guarantees high-frequency high-speed printed circuit board in the signal integrity of signals transmission.
Description
Technical field
The present invention relates to printed wiring board manufacture technology fields, and in particular to a kind of accurate controlled depth milling of microwave printed circuit plate
The production method of slot.
Background technique
With the development of science and technology electronic product has become indispensable articles for daily use in for people's lives, and printed circuit
Plate (Printed Circuit Board, abbreviation PCB) is the important component of electronic product, and people produce electronics in recent years
The functional requirement of product is more and more, and thus to PCB, higher requirements are also raised, generally for special convenient for installing on PCB
The device that the device or needs of function sink, it is often necessary to which stepped groove is set on PCB, and stepped groove is also to realize the big function of product
The pith of rate heat dissipation, is in industry widely used.
In the prior art, stepped groove usually pass through molding gong plate control, using cover the methods of epiphragma make, this method
It has the disadvantage in that and is made of molding gong plate mode, can not accurately be accomplished after not hurting next layer of substrate or fluting after slotting
Non- gong is to target substrate layer, while tolerance when also can not well control production pcb board；And it utilizes and covers the production of the methods of epiphragma
In the process, pcb board can be thickeied, causing pcb board thickness is more than tolerance risk, does not meet production standard, and this production
Method flow is cumbersome, and production efficiency is low.
Summary of the invention
It is an object of the invention to provide a kind of accurate controlled depth milling of microwave printed circuit plate to overcome existing technological deficiency
The production method of slot guarantees that high-frequency high-speed printed circuit board exists using the method achieve zero damage of Rogers high frequency plate
The signal integrity of signals transmission.
In order to solve the above-mentioned technical problems, the present invention provides a kind of production of the accurate controlled depth milling slot of microwave printed circuit plate
Method, comprising the following steps:
S1, stepped groove is formed on production plate by way of controlled depth milling slot；Produce outermost Jie of plate wherein side
Matter layer is Rogers high frequency plate, and the stepped groove is by gong shape under another side for laterally having Rogers high frequency plate of production plate
At, and the slot bottom of the stepped groove is located on the inside of Rogers high frequency plate in the dielectric layer on layers of copper top；
S2, heavy copper and electric plating of whole board processing are carried out to production plate, the slot bottom of stepped groove and cell wall is made to plate one layer of layers of copper；
S3, the pad pasting on production plate then form outer-layer circuit figure on production plate by exposing, being developed in, then right
It produces plate and carries out graphic plating；
S4, gong remove the electroplated layer of stepped groove slot bottom, expose the dielectric layer of slot bottom；
S5, the dielectric layer that stepped groove slot bottom is burnt up by laser, expose the layers of copper on the inside of Rogers high frequency plate；
S6, production plate is carried out except the layers of copper for after glue processing, passing through exposing at alkali etching removing stepped groove slot bottom.
Preferably, in step S1,50 μm of < of thickness more than the dielectric layer of stepped groove slot bottom.
Preferably, in step S5, size range when laser burns dielectric layer is more unilateral than stepped groove size in step S1 big
0.02mm。
Preferably, in the step S4, in step S5, the laser is not burn copper laser, lasing beam diameter 0.4mm.
Preferably, in step S6, using plasma except glue handle except glue to production plate.
Preferably, in step S6, the speed of production plate overetch line is 4.5m/min.
It preferably, further include successively carrying out moving back tin, outer layer etching, outer layer optical detection, system to production plate after step S6
The step of making solder mask, surface treatment and molding, is made microwave printed circuit plate.
Preferably, it by multiple core plates and a dielectric layer is Rogers high frequency plate that the production plate, which is by prepreg,
The multi-layer board that core plate is press-fitted together as one, and Rogers high frequency plate is located at multiple-plate side, and multi-layer board step S1 it
Before have been subjected to drilling processing.
Preferably, the core plate has made internal layer circuit before pressing, and is Rogers high frequency plate in dielectric layer
When making internal layer circuit on core plate, retain the layers of copper at corresponding ladder groove location.
Compared with prior art, the invention has the following beneficial effects:
The present invention is in the electroplated layer of gong stepped groove and gong ladder trench bottom on producing plate, stepped groove during gong slot twice
Bottom control the thickness internal in dielectric layer, then again by laser burn up slot bottom expose dielectric layer, etch again later
The layers of copper on the inside of Rogers high frequency plate is removed, zero damage of Rogers high frequency plate is realized by above procedure, is guaranteed high
Signal integrity of the frequency High-Speed Printed Circuit Board in signals transmission；And the size range by controlling laser burning dielectric layer,
Increase except the process that is first once etched to slot bottom layers of copper before glue processing and outer layer etching, it is ensured that stepped groove slot bottom dielectric layer with
Zero residual of layers of copper.
Detailed description of the invention
Fig. 1 is the schematic diagram for forming stepped groove in embodiment on production plate；
Fig. 2 is schematic diagram of the stepped groove after heavy copper, electric plating of whole board and graphic plating in embodiment；
Fig. 3 is the schematic diagram that stepped groove slot bottom electroplated layer is removed in embodiment；
Fig. 4 is the schematic diagram that laser removes dielectric layer in embodiment；
Fig. 5 is the schematic diagram that layers of copper on the inside of Rogers high frequency plate in stepped groove is removed in embodiment.
Specific embodiment
In order to more fully understand technology contents of the invention, below in conjunction with specific embodiment to technical side of the invention
Case is described further and illustrates.
Embodiment
The present embodiment provides a kind of production methods of wiring board, including the accurate controlled depth milling slot of microwave printed circuit plate
Production method, the specific process is as follows:
(1), sawing sheet: outputing four core plates by jigsaw size 520mm × 620mm, as shown in Figure 1, four core plates are respectively
L1-L2 layer, L3-L4 layers, L5-L6 layers, L7-L8 layers in figure, wherein the dielectric layer of L7-L8 layers of core plate is Rogers high frequency plate
Material.
(2), internal layer circuit production (negative film technique): inner figure transfer is coated on core plate photosensitive with vertical application machine
Film, 8 μm of the film thickness monitoring of light-sensitive surface are completed on core plate using Full-automatic exposure machine with 5-6 lattice exposure guide rule (21 lattice exposure guide rule)
Internal layer circuit exposure；Core plate after exposure development is etched internal layer circuit by internal layer etching, and it is 3mil that internal layer line width, which measures,；It is interior
Then layer AOI checks the defects of opening short circuit, route notch, route pin hole of internal layer circuit, defective to scrap processing, zero defect
Product go out to downstream；Wherein when making internal layer circuit on L7-L8 layers of core plate, retain the copper at corresponding ladder groove location
Layer.
(3), press: (specific plate-laying sequence is core from top to bottom after four core plates are superimposed together in advance with prepreg
Plate, prepreg, core plate, prepreg, core plate, prepreg, core plate), lamination item appropriate is then selected according to plate Tg
Part presses superimposed sheet, forms production plate；Wherein L7-L8 layers of core plate are in the wherein side of production plate.
(4), outer layer drills: being drilled on production plate according to borehole data using the mode of machine drilling.
(5), gong slot: as shown in Figure 1, from a side of production plate to there is Rogers high frequency plate by way of controlled depth milling slot
Gong forms stepped groove 2 under 1 side；And the slot bottom of stepped groove 2 is located at the dielectric layer on 1 inside layers of copper top of Rogers high frequency plate
In (i.e. prepreg)；And 50 μm of < of thickness more than the dielectric layer of stepped groove slot bottom.
(6), heavy copper: depositing one layer of thin copper on the cell wall and slot bottom of hole wall and stepped groove by way of chemical reaction,
There is provided basis for subsequent electric plating of whole board, backlight tests 10 grades, sink copper with a thickness of 0.5 μm.
(7), electric plating of whole board: according to the mechanism of electrochemical reaction, upper one layer of copper is electroplated on the basis of heavy copper, thickeies ladder
Layers of copper and hole copper in slot.
(8), outer-layer circuit (positive blade technolgy) is made: specifically includes the following steps:
S1, dry film is pasted on production plate, then the production plate after patch dry film is exposed using automatic exposure machine, with 5-
7 lattice exposure guide rules (21 lattice exposure guide rule) complete outer-layer circuit exposure, form outer-layer circuit figure on production plate after developed, then
Graphic plating (successively carrying out copper facing and tin plating) is carried out on production plate, and electroplating parameter is set according to desired completion copper thickness,
Copper facing is the current density electric plating of whole board 50min with 2.3ASD, and surface copper thickness >=30um, tin plating is the current density with 1.0ASD
8min, 5-8 μm of tin thickness is electroplated；To form electroplated layer 3 (as shown in Figure 2) in the cell wall and slot bottom of stepped groove 2；
S4, gong remove the electroplated layer 3 of 2 slot bottom of stepped groove, expose the dielectric layer 4 (as shown in Figure 3) of slot bottom；
S5, the dielectric layer that stepped groove slot bottom is burnt up by not burning copper laser, expose the layers of copper 5 on the inside of Rogers high frequency plate
(as shown in Figure 4), lasing beam diameter 0.4mm；And laser burn dielectric layer when size range than gong stepped groove when size list
The big 0.02mm in side, it is ensured that the dielectric layer in stepped groove is completely burned off.
S6, using plasma except glue to production plate carry out except glue processing after, by alkali etching remove stepped groove slot bottom at
The layers of copper 5 of exposing, to expose Rogers high frequency plate 1 (as shown in Figure 5), the speed of production plate overetch line is when etching
4.5m/min；
S7, then film is successively moved back again, etches and move back tin, etch outer-layer circuit on production plate；Outer layer AOI, using certainly
Dynamic Systems for optical inspection detects whether outer-layer circuit has open circuit, notch, etching not clean, short-circuit by the comparison with CAM data
The defects of.
(9), welding resistance, silk-screen character: by making green oil layer and silk-screen character, green oil thickness are as follows: 10- in production plate outer layer
50 μm, so as to so that production plate can reduce influence of the environmental change to it in the subsequent use process.
(10), surface treatment (heavy nickel gold): principle is learned in pad copper face Tonghua of welding resistance windowing position, and uniform deposition centainly requires
The nickel layer and layer gold of thickness, nickel layer thickness are as follows: 3-5 μm；Layer gold thickness are as follows: 0.05-0.1 μm.
(11), it forms: according to the prior art and pressing design requirement gong shape, route is made in the +/- 0.05mm of external form tolerance
Plate.
(12), electrical testing: testing the electrically conducting performance of production board, this plate uses test method are as follows: flying probe.
(13), FQC: appearance, hole copper thickness, thickness of dielectric layers, green oil thickness, internal layer copper thickness of production board etc. are checked whether
Meet the requirement of client.
(14), it packs: according to the manner of packing and packaging quantity of customer requirement, packaging being sealed to production board, and
It is allowed to dry drying prescription and humidity card, then shipment.
It is provided for the embodiments of the invention technical solution above to be described in detail, specific case used herein
The principle and embodiment of the embodiment of the present invention are expounded, the explanation of above embodiments is only applicable to help to understand this
The principle of inventive embodiments；At the same time, for those skilled in the art, according to an embodiment of the present invention, in specific embodiment party
There will be changes in formula and application range, in conclusion the contents of this specification are not to be construed as limiting the invention.
Claims (9)
1. a kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate, which comprises the following steps:
S1, stepped groove is formed on production plate by way of controlled depth milling slot；Produce the outermost dielectric layer of plate wherein side
For Rogers high frequency plate, the stepped groove is formed by gong under another side for laterally having Rogers high frequency plate of production plate,
And the slot bottom of the stepped groove is located on the inside of Rogers high frequency plate in the dielectric layer on layers of copper top；
S2, heavy copper and electric plating of whole board processing are carried out to production plate, the slot bottom of stepped groove and cell wall is made to plate one layer of layers of copper；
S3, the pad pasting on production plate then form outer-layer circuit figure on production plate by exposing, being developed in, then to production
Plate carries out graphic plating；
S4, gong remove the electroplated layer of stepped groove slot bottom, expose the dielectric layer of slot bottom；
S5, the dielectric layer that stepped groove slot bottom is burnt up by laser, expose the layers of copper on the inside of Rogers high frequency plate；
S6, production plate is carried out except the layers of copper for after glue processing, passing through exposing at alkali etching removing stepped groove slot bottom.
2. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that step
In S1,50 μm of < of thickness more than the dielectric layer of stepped groove slot bottom.
3. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that step
In S5, laser burn dielectric layer when size range it is big 0.02mm more unilateral than the stepped groove size in step S1.
4. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that described
In step S4, in step S5, the laser is not burn copper laser, lasing beam diameter 0.4mm.
5. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that step
In S6, using plasma except glue handle except glue to production plate.
6. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that step
In S6, the speed of production plate overetch line is 4.5m/min.
7. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that step
Further include after S6 successively to production plate move back tin, outer layer etching, outer layer optical detection, production solder mask, be surface-treated and
Microwave printed circuit plate is made in the step of molding.
8. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 1, which is characterized in that described
Production plate is more to be press-fitted together as one the core plate that multiple core plates and a dielectric layer are Rogers high frequency plate by prepreg
Laminate, and Rogers high frequency plate is located at multiple-plate side, and multi-layer board has been subjected to drilling processing before step S1.
9. the production method of the accurate controlled depth milling slot of microwave printed circuit plate according to claim 8, which is characterized in that described
Core plate has made internal layer circuit before pressing, and makes internal layer circuit on the core plate that dielectric layer is Rogers high frequency plate
When, retain the layers of copper at corresponding ladder groove location.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811121354.6A CN109121300A (en) | 2018-09-25 | 2018-09-25 | A kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811121354.6A CN109121300A (en) | 2018-09-25 | 2018-09-25 | A kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate |
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| CN109121300A true CN109121300A (en) | 2019-01-01 |
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| CN201811121354.6A Pending CN109121300A (en) | 2018-09-25 | 2018-09-25 | A kind of production method of the accurate controlled depth milling slot of microwave printed circuit plate |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112449478A (en) * | 2019-08-27 | 2021-03-05 | 深南电路股份有限公司 | Circuit board and manufacturing method thereof |
| CN112654153A (en) * | 2020-11-12 | 2021-04-13 | 惠州市金百泽电路科技有限公司 | Processing method of high-precision light wave scale PCB of measurement and control equipment |
| CN114916146A (en) * | 2022-05-05 | 2022-08-16 | 深圳明阳电路科技股份有限公司 | PCB manufacturing method and PCB |
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| CN103298245A (en) * | 2013-06-14 | 2013-09-11 | 东莞生益电子有限公司 | Manufacture method for high-frequency circuit board and circuit board manufactured through method |
| CN103313512A (en) * | 2013-07-03 | 2013-09-18 | 中国船舶重工集团公司第七二四研究所 | Microwave assembly high-density substrate design method based on composite dielectric materials |
| CN105163526A (en) * | 2015-08-21 | 2015-12-16 | 深圳崇达多层线路板有限公司 | Manufacturing method of stepped grooves, and printed circuit board comprising stepped grooves |
-
2018
- 2018-09-25 CN CN201811121354.6A patent/CN109121300A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103298245A (en) * | 2013-06-14 | 2013-09-11 | 东莞生益电子有限公司 | Manufacture method for high-frequency circuit board and circuit board manufactured through method |
| CN103313512A (en) * | 2013-07-03 | 2013-09-18 | 中国船舶重工集团公司第七二四研究所 | Microwave assembly high-density substrate design method based on composite dielectric materials |
| CN105163526A (en) * | 2015-08-21 | 2015-12-16 | 深圳崇达多层线路板有限公司 | Manufacturing method of stepped grooves, and printed circuit board comprising stepped grooves |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112449478A (en) * | 2019-08-27 | 2021-03-05 | 深南电路股份有限公司 | Circuit board and manufacturing method thereof |
| CN112449478B (en) * | 2019-08-27 | 2022-03-04 | 深南电路股份有限公司 | Circuit board and manufacturing method thereof |
| CN112654153A (en) * | 2020-11-12 | 2021-04-13 | 惠州市金百泽电路科技有限公司 | Processing method of high-precision light wave scale PCB of measurement and control equipment |
| CN114916146A (en) * | 2022-05-05 | 2022-08-16 | 深圳明阳电路科技股份有限公司 | PCB manufacturing method and PCB |
| CN114916146B (en) * | 2022-05-05 | 2024-05-17 | 深圳明阳电路科技股份有限公司 | PCB manufacturing method and PCB |
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