CN108811344A - A kind of FPC blind holes detection method - Google Patents

A kind of FPC blind holes detection method Download PDF

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Publication number
CN108811344A
CN108811344A CN201810877238.0A CN201810877238A CN108811344A CN 108811344 A CN108811344 A CN 108811344A CN 201810877238 A CN201810877238 A CN 201810877238A CN 108811344 A CN108811344 A CN 108811344A
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CN
China
Prior art keywords
fpc
blind hole
concentration
shadow
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201810877238.0A
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Chinese (zh)
Inventor
高清宇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kinwong Electronic Technology Longchuan Co Ltd
Original Assignee
Kinwong Electronic Technology Longchuan Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kinwong Electronic Technology Longchuan Co Ltd filed Critical Kinwong Electronic Technology Longchuan Co Ltd
Priority to CN201810877238.0A priority Critical patent/CN108811344A/en
Publication of CN108811344A publication Critical patent/CN108811344A/en
Pending legal-status Critical Current

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Classifications

    • 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
    • H05K3/0047—Drilling of holes
    • 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
    • H05K3/22—Secondary treatment of printed circuits
    • H05K3/26—Cleaning or polishing of the conductive pattern
    • 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
    • H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
    • H05K3/42—Plated through-holes or plated via connections
    • H05K3/421—Blind plated via connections
    • 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
    • H05K2203/07—Treatments involving liquids, e.g. plating, rinsing
    • H05K2203/0779—Treatments involving liquids, e.g. plating, rinsing characterised by the specific liquids involved
    • H05K2203/0786—Using an aqueous solution, e.g. for cleaning or during drilling of holes
    • H05K2203/0793—Aqueous alkaline solution, e.g. for cleaning or etching
    • 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
    • H05K2203/07—Treatments involving liquids, e.g. plating, rinsing
    • H05K2203/0779—Treatments involving liquids, e.g. plating, rinsing characterised by the specific liquids involved
    • H05K2203/0786—Using an aqueous solution, e.g. for cleaning or during drilling of holes
    • H05K2203/0796—Oxidant in aqueous solution, e.g. permanganate
    • 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
    • H05K2203/09—Treatments involving charged particles
    • H05K2203/095—Plasma, e.g. for treating a substrate to improve adhesion with a conductor or for cleaning holes
    • 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
    • H05K2203/16—Inspection; Monitoring; Aligning
    • H05K2203/163—Monitoring a manufacturing process

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Printing Elements For Providing Electric Connections Between Printed Circuits (AREA)

Abstract

The present invention provides a kind of FPC blind holes detection methods, it is related to wiring board manufacturing technology field, this method specifically includes drilling, plasma cleaning, chemical cleaning, shadow, AOI scannings, to carry out full-automatic optical detection scanning to entire FPC, detects the blind hole quality of entire FPC.Directly all blind holes can be detected using this method, rapidly and efficiently.

Description

A kind of FPC blind holes detection method
Technical field
The present invention relates to printed circuit board technology fields, refer in particular to a kind of FPC blind holes detection method.
Background technology
As electronic product more tends to be lightening, flexible circuit board has gradually come into the sight of numerous electronics firms, soft Property wiring board abbreviation FPC.In FPC drilling processings field, there are two kinds of conventional machining techniques：Machine drilling, laser drill, the former It is generally used for making through-hole, then through-hole, blind hole can all make the latter.By the unique processed edge of laser drill, blind hole product Gradually introduced by major wiring board manufacturer.
Blind hole is set, reduces through-hole, more spaces can be provided for FPC cablings, remaining space can be used as large area screen Purposes is covered, improves the properties of printed circuit board whereby.Blind hole no doubt has unique advantage, but after ensureing its copper facing Quality OK but has certain difficulty, and most companies are not perfect for the quality restriction standard of blind hole at present, mostly use system greatly The mode for making micro- slice sampling observation confirms that blind hole plates copper mass, and this mode is only accomplished the part monitoring of blind hole quality, caused blind Hole product is susceptible to quality careless mistake, can not 100% verify hole bottom residue glue, bottom hole carbon residue, blind hole dislocation etc. qualities lack It falls into.
Invention content
The technical problem to be solved by the present invention is to：The upper blind hole test problems of FPC.
In order to solve the above-mentioned technical problem, the invention discloses a kind of FPC blind holes detection method, this method specifically include as Lower step：
Drilling, in drilling through blind hole on FPC；
Plasma cleaning, the above-mentioned blind hole drilled through using plasma cleaning remove impurity；
Chemical cleaning recycles chemical mode to clean the above-mentioned blind hole after plasma cleaning, further removes impurity；
Shadow, then shadow processing is carried out to the blind hole after cleaning；
AOI is scanned, and is carried out full-automatic optical detection scanning to entire FPC, is detected the blind hole quality of entire FPC.
Further, in the AOI scanning steps, by scanning information being compared with preset blind hole information point Analysis, obtains the quality conditions of all blind holes on entire FPC.
Further, it in the plasma cleaning step, including cleans for the first time, plasma is by N used in the stage2、CF4 And O2Any one dissociative ionization in gas obtains, and scavenging period is 8 ± 2min.
Further, further include second of cleaning in the plasma cleaning step, plasma is by O used in the stage2Gas Body dissociative ionization obtains, and scavenging period is 3 ± 2min.
Further, in the chemical cleaning step, including spray degreaser carries out oil removing to FPC, and degreaser includes The H of a concentration of 2%-6%2SO4, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 40 DEG C ± 2 DEG C.
Further, in the chemical cleaning step, after oil removing, also packet spray micro-etching agent carries out microetch, micro-etching agent to FPC Include the H of a concentration of 11g/L-15g/L2O2, a concentration of 10g/L-50g/L H2SO4With the Cu of concentration≤48g/L2+, spray Pressure is 0.8kg/cm2-1.0kg/cm2, temperature is 30 DEG C ± 2 DEG C, and microetch amount is 0.5 μm -0.7 μm.
Further, further include that pickling, pickling are carried out to FPC using mordant after microetch in the chemical cleaning step Agent includes the H of a concentration of 0.8%-2.4%2SO4, temperature is room temperature.
Further, in the shadow step, including shadow agent is used, solid content is 3.5%- in shadow agent 4.5%, viscosity≤8CP, PH 8.5-9.2, electrical conductivity is 300 μ s/cm-1500 μ s/cm, and temperature is 21-25 DEG C.
Further, further include being fixed to FPC spray fixer in the shadow step, and the equivalent of fixer A concentration of 0.1N-0.18N, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 43-47 DEG C.
Further, further include that spray back segment micro-etching agent carries out back segment microetch, back segment after fixing in the shadow step Micro-etching agent includes the H of a concentration of 3%-7%2O2, a concentration of 10g/L-50g/L H2SO4, spray pressure 1.0kg/cm2- 1.2kg/cm2, temperature is 30-34 DEG C, and microetch amount ED copper is 1.1 ± 0.1 μm and RA/JA copper is 1.5 ± 0.1 μm.
In compared with the prior art by way of making micro- slice sampling observation, FPC blind holes detection method disclosed in this programme, Can 100% full inspection blind hole shadow metapore bottom graphite remain situation, prevent the quality abnormal of blind hole copper facing metapore bottom black surround in advance. Whether the reliability that can also examine radium-shine blind drilled parameter, the radium-shine parameter of judgement that can be simple and clear using the technology have volume production item Part.And it can greatly shorten the time for examining blind hole quality, greatly improve the production efficiency of blind hole plate, operation is also more simple Just.
Description of the drawings
The detailed process of the present invention is described in detail below in conjunction with the accompanying drawings
Fig. 1 is the flow chart of FPC blind holes of the present invention detection.
Specific implementation mode
To explain the technical content, the achieved purpose and the effect of the present invention in detail, below in conjunction with embodiment and coordinate attached Figure is explained in detail.
In conjunction with attached drawing 1, in one embodiment, disclose a kind of FPC blind holes detection method, this method specifically include as Lower step：
Drilling, is to drill through blind hole on FPC, laser mode specifically can be used and form blind hole.Certainly, before drilling Can also include the sawing sheet of wiring board and other existing normal process steps.But because this programme innovative point is the detection of blind hole, therefore it Preceding normal process steps just repeat no more.The blind hole drilled through herein, bottom hole normal condition are metal copper layer, but generally can be residual in hole Stay thin glue, carbon residue.
Plasma cleaning, the above-mentioned blind hole drilled through using plasma cleaning remove impurity.Impurity therein specifically includes Dust, glue residue and carbon dust in hole etc..Plasma cleaning step includes cleaning for the first time, and plasma is by N used in the stage2、 CF4And O2Any one dissociative ionization in gas obtains, and scavenging period is 8 ± 2min.Further include in plasma cleaning step Secondary cleaning, plasma used in the stage is by O2Gaseous dissociation ionizes to obtain, and scavenging period is 3 ± 2min, and design parameter is shown in Table 1。
Table 1
Chemical cleaning recycles chemical mode to clean the above-mentioned blind hole after plasma cleaning, further removes impurity. Other than removing above-mentioned impurity, chemical cleaning method can also remove some oxides.Chemical cleaning step includes allowing FPC mistakes Except oil cylinder, spray degreaser carries out oil removing to FPC at except oil cylinder, and degreaser includes the H of a concentration of 2%-6%2SO4, spray Pressure is 0.8kg/cm2-1.0kg/cm2, temperature is 40 DEG C ± 2 DEG C.In chemical cleaning step, after oil removing, also packet makes FPC excessively micro- Cylinder is lost, micro-etching agent is sprayed at microetch cylinder, microetch is carried out to FPC, micro-etching agent includes the H of a concentration of 11g/L-15g/L2O2, it is dense Degree is the H of 10g/L-50g/L2SO4With the Cu of concentration≤48g/L2+, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 30 DEG C ± 2 DEG C, and microetch amount is 0.5 μm -0.7 μm.Further include allowing FPC overpickling cylinders after microetch in chemical cleaning step, Pickling is carried out to FPC using mordant at pickling cylinder, mordant includes the H of a concentration of 0.8%-2.4%2SO4, temperature is normal Temperature.Design parameter is shown in Table 2.
Table 2
Shadow, then shadow processing is carried out to the blind hole after cleaning.Shadow method (shadow) is main to be made using graphite For conductive body.Due in graphitic molecules structure, there is a large amount of free electrons, therefore the electric conductivity of graphite is turned to than general carbon black It is high.And electroplating velocity is directly proportional with conductive coating performance, so conductive coating performance is higher, electroplating velocity is faster.It should In step, including FPC is allowed to be handled through shadow cylinder, fixing cylinder and back segment microetch cylinder successively.In shadow cylinder, including use black Shadow agent, solid content is 3.5%-4.5% in shadow agent, and viscosity≤8CP, PH 8.5-9.2, electrical conductivity is 300 μ s/cm- 1500 μ s/cm, temperature are 21-25 DEG C.It is fixed in being fixed cylinder, including to FPC spray fixer, and the equivalent of fixer A concentration of 0.1N-0.18N, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 43-47 DEG C.In back segment microetch cylinder, packet It includes spray back segment micro-etching agent and carries out back segment microetch, back segment micro-etching agent includes the H of a concentration of 3%-7%2O2, a concentration of 10g/L- The H of 50g/L2SO4, spray pressure 1.0kg/cm2-1.2kg/cm2, temperature be 30-34 DEG C, and microetch amount ED copper be 1.1 ± 0.1 μm is 1.5 ± 0.1 μm with RA/JA copper.Specific technological parameter is shown in Table 3.
Table 3
AOI is scanned, and is carried out full-automatic optical detection scanning to entire FPC, is detected the blind hole quality of entire FPC.The step In, by the way that scanning information and preset blind hole information to be compared, obtain the quality feelings of all blind holes on entire FPC Condition.According to the design of FPC, for entire FPC, there are one specific blind hole presupposed informations, including each blind hole is on FPC Spatial position distributed intelligence, the aperture of each blind hole, each blind hole hole depth etc., and can by these information formed a data Packet.When AOI Scanning Detctions, by the light reflection situation of entire FPC plate faces each position, the practical letter of plate face blind hole can be learned Breath.And can be compared with presupposed information, judge whether qualification etc..
In the present solution, after drilling through blind hole, impurity in blind hole is removed by plasma and chemical cleaning mode.Then pass through Shadow may make PI, PP transparent or reflective in hole or other gelatin substance adsorption carbon dust and no longer transparent or reflective, from And the interference that these substances detect blind hole AOI can be excluded.So that using AOI be scanned the obtained result of detection more subject to Really, credible, so as to fast and effeciently detect, which blind hole is qualified blind hole on FPC plates, which blind hole is unqualified blind hole.
It should be noted that example the above is only the implementation of the present invention, is not intended to limit the scope of the invention, It is every to utilize equivalent structure or equivalent flow shift made by description of the invention and accompanying drawing content, it is applied directly or indirectly in Other related technical areas are included within the scope of the present invention.

Claims (10)

1. a kind of FPC blind holes detection method, it is characterised in that：Including
Drilling, in drilling through blind hole on FPC；
Plasma cleaning, the above-mentioned blind hole drilled through using plasma cleaning remove impurity；
Chemical cleaning recycles chemical mode to clean the above-mentioned blind hole after plasma cleaning, further removes impurity；
Shadow, then shadow processing is carried out to the blind hole after cleaning；
AOI is scanned, and is carried out full-automatic optical detection scanning to entire FPC, is detected the blind hole quality of entire FPC.
2. the method as described in claim 1, it is characterised in that：In the AOI scanning steps, by by scanning information with it is default Blind hole information be compared, obtain the quality conditions of all blind holes on entire FPC.
3. the method as described in claim 1, it is characterised in that：In the plasma cleaning step, including clean for the first time, it should Plasma is by N used in stage2、CF4And O2Any one dissociative ionization in gas obtains, and scavenging period is 8 ± 2min.
4. method as claimed in claim 3, it is characterised in that：Further include second of cleaning in the plasma cleaning step, Plasma is by O used in the stage2Gaseous dissociation ionizes to obtain, and scavenging period is 3 ± 2min.
5. the method as described in claim 1, it is characterised in that：In the chemical cleaning step, including spray degreaser is to FPC Oil removing is carried out, degreaser includes the H of a concentration of 2%-6%2SO4, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 40℃±2℃。
6. method as claimed in claim 5, it is characterised in that：In the chemical cleaning step, after oil removing, also packet sprays microetch Agent carries out microetch to FPC, and micro-etching agent includes the H of a concentration of 11g/L-15g/L2O2, a concentration of 10g/L-50g/L H2SO4With The Cu of concentration≤48g/L2+, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature is 30 DEG C ± 2 DEG C, and microetch amount is 0.5 μ m-0.7μm。
7. method as claimed in claim 6, it is characterised in that：Further include utilizing acid after microetch in the chemical cleaning step Lotion carries out pickling to FPC, and mordant includes the H of a concentration of 0.8%-2.4%2SO4, temperature is room temperature.
8. the method as described in claim 1, it is characterised in that：In the shadow step, including shadow agent is used, in shadow agent Solid content is 3.5%-4.5%, viscosity≤8CP, PH 8.5-9.2, and electrical conductivity is 300 μ s/cm-1500 μ s/cm, temperature It is 21-25 DEG C.
9. method as claimed in claim 8, it is characterised in that：In the shadow step, further include to FPC spray fixer into Row fixing, and the equivalent concentration of fixer is 0.1N-0.18N, spray pressure 0.8kg/cm2-1.0kg/cm2, temperature 43- 47℃。
10. method as claimed in claim 9, it is characterised in that：Further include spray back segment after fixing in the shadow step Micro-etching agent carries out back segment microetch, and back segment micro-etching agent includes the H of a concentration of 3%-7%2O2, a concentration of 10g/L-50g/L H2SO4, spray pressure 1.0kg/cm2-1.2kg/cm2, temperature be 30-34 DEG C, and microetch amount ED copper be 1.1 ± 0.1 μm and RA/JA copper is 1.5 ± 0.1 μm.
CN201810877238.0A 2018-08-03 2018-08-03 A kind of FPC blind holes detection method Pending CN108811344A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110769606A (en) * 2019-11-13 2020-02-07 珠海景旺柔性电路有限公司 Double-sided processing method suitable for single-sided copper-plated panel

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104737629A (en) * 2013-07-15 2015-06-24 深圳崇达多层线路板有限公司 Resistance welding pretreatment process and preparation process of high-frequency PCB
CN105744746A (en) * 2014-12-12 2016-07-06 统赢软性电路(珠海)有限公司 Manufacture method of single-sided FPC board
CN106132116A (en) * 2016-07-05 2016-11-16 广州美维电子有限公司 A kind of wiring board blind hole fills out process for copper
CN106163102A (en) * 2015-04-02 2016-11-23 富葵精密组件(深圳)有限公司 Flexible PCB and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104737629A (en) * 2013-07-15 2015-06-24 深圳崇达多层线路板有限公司 Resistance welding pretreatment process and preparation process of high-frequency PCB
CN105744746A (en) * 2014-12-12 2016-07-06 统赢软性电路(珠海)有限公司 Manufacture method of single-sided FPC board
CN106163102A (en) * 2015-04-02 2016-11-23 富葵精密组件(深圳)有限公司 Flexible PCB and preparation method thereof
CN106132116A (en) * 2016-07-05 2016-11-16 广州美维电子有限公司 A kind of wiring board blind hole fills out process for copper

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110769606A (en) * 2019-11-13 2020-02-07 珠海景旺柔性电路有限公司 Double-sided processing method suitable for single-sided copper-plated panel
CN110769606B (en) * 2019-11-13 2021-02-19 珠海景旺柔性电路有限公司 Double-sided processing method suitable for single-sided copper-plated panel

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Application publication date: 20181113