Thawj kauj ruam ntawm PCB production is to organize and check the PCB Layout. Lub tshuab tsim khoom PCB tau txais CAD cov ntaub ntawv los ntawm tuam txhab tsim PCB. Txij li txhua CAD software muaj nws tus kheej cov ntawv tshwj xeeb, cov PCB cog tau hloov lawv mus rau hauv cov ntawv sib koom ua ke-Txuas ntxiv Gerber RS-274X lossis Gerber X2. Then the engineer of the factory will check whether the PCB layout conforms to the production process, whether there are any defects and other problems.

Hauv ib qho ntawm PCBS ua tsev, PCB txheej txheem tau luam tawm ntawm daim ntawv siv lub tshuab luam ntawv laser thiab tom qab ntawd hloov mus rau lub rooj tsav tooj liab. Txawm li cas los xij, hauv cov txheej txheem luam ntawv, vim tias lub tshuab luam ntawv nquag ua rau tsis muaj qhov tsis txaus, nws yog qhov yuav tsum tau sau tus lej nrog tus cwj mem roj.

Ib qho me me ntawm kev tsim khoom yog qhov zoo, tab sis yog tias qhov tsis xws luag no raug xa mus rau kev tsim khoom lag luam, nws yuav txo qis kev ua haujlwm zoo. Therefore, the factory generally adopts the way of photocopying, printing the PCB layout on the film. If it is a multi-layer PCB, the layout of each layer will be arranged in order.

Tom qab ntawd zaj duab xis raug ntaus nrog lub qhov taw tes tawm tsam. Counterpoint holes are very important, and are then used to align materials on each layer of the PCB.

Kev tsim khoom ntawm pawg thawj coj

Clean the copper clad plate, if dust may cause the final circuit short circuit or break.

The figure below is an illustration of an 8-layer PCB, which is actually made up of 3 copper-clad plates (core boards) plus 2 copper films and then glued together with semi-cured sheets. The production sequence starts from the core board (four or five layers of lines) in the middle, and is continuously stacked together before being fixed. 4-txheej PCB tau ua zoo sib xws, tab sis tsuas muaj ib lub phaj thiab ob daim duab tooj liab xwb.

Transfer of inner PCB layout

Therefore, the two-layer circuit of the most central Core plate should be made first. After the copper-clad plate is cleaned, the surface is covered with a photosensitive film. Cov yeeb yaj kiab ua kom khov thaum raug lub teeb, ua ib zaj duab xis tiv thaiv cov ntawv ci tooj liab ntawm cov phaj tooj liab.

Insert two layers of PCB layout film and two layers of copper clad board, and finally insert the upper layer of PCB layout film to ensure that the upper and lower layers of PCB layout film stacking position is accurate.

Photosensitizer uses UV lamp to irradiate the photosensitive film on copper foil. The photosensitive film is solidified under the transparent film, and the photosensitive film is not solidified under the opaque film. The copper foil covered by solidified photosensitive film is the PCB layout line needed, equivalent to the role of laser printer ink of manual PCB. Hauv daim ntawv PCB txheej txheem ntawm lub tshuab luam ntawv laser dhau los, cov xim dub tau npog nrog cov ntawv tooj liab kom khaws cia. In this case, the copper foil covered with black film will corrode away, while the transparent film will be preserved as the photosensitive film solidifies.

Cov yeeb yaj kiab uas tsis tau kho yog tom qab ntawd yaug nrog cov lye thiab cov txheej txheem tooj liab uas yuav tsum tau npog los ntawm zaj duab xis kho.

Inner core board etching

The unwanted copper foil is then etched away with a strong base, such as NaOH.

Tear off the cured photosensitive film to expose the copper foil needed for PCB layout circuit.

Core phaj drilling thiab tshuaj xyuas

Cov tub ntxhais phaj tau ua tiav. Then make the opposite hole in the core plate for easy alignment with other raw materials.

Once the core board is pressed with other layers of PCB, it cannot be modified, so it is very important to check. Lub tshuab yuav cia li sib piv nrog PCB teeb duab kos los tshuaj xyuas qhov ua yuam kev.

Thawj ob txheej txheej ntawm PCB cov laug cam tau ua

laminated

Ntawm no peb xav tau cov khoom siv raw tshiab hu ua semi-cured sheet (Prepreg), uas yog pawg thawj coj saib xyuas thiab pawg thawj coj (PCB txheej lej & GT; 4), thiab cov nplaum ntawm cov phaj tub ntxhais thiab cov ntawv ci tooj liab sab nraud, tab sis kuj tseem ua lub luag haujlwm hauv rwb thaiv tsev.

Cov txheej qis ntawm cov ntawv ci tooj liab thiab ob txheej ntawm cov ntawv ib nrab ua kom ruaj khov tau ua ntej dhau los ntawm qhov chaw tso thiab qis phaj phaj ruaj khov txoj haujlwm, thiab tom qab ntawd cov tub ntxhais zoo phaj kuj tseem muab tso rau hauv qhov chaw, thiab thaum kawg tig ob txheej ntawm cov ntawv ib nrab ua kom khov, txheej txheej ntawm cov ntawv ci tooj liab thiab txheej txheej siab aluminium phaj npog ntawm cov phaj phaj.

In order to improve work efficiency, the factory will stack three different PCB boards together and then fix them. The upper iron plate is magnetically attracted to facilitate counterpoint with the lower iron plate. Los ntawm kev tso cov koob tshuaj tiv thaiv, ob txheej txheej ntawm cov hlau phaj counterpoint ua tiav, lub tshuab kom deb li sai tau kom nrawm qhov chaw nruab nrab ntawm cov phaj hlau, thiab tom qab ntawd kho nrog cov ntsia hlau.

PCB board clamped by iron plate is placed on the support, and then into the vacuum hot press for lamination. The heat in the vacuum hot press melts the epoxy resin in the semi-cured sheet, holding the core and copper foil together under pressure.

After laminating, remove the top iron plate that presses the PCB. Tom qab ntawd cov phaj siab aluminium tau raug tshem tawm. Cov phaj txhuas tseem ua lub luag haujlwm hauv kev cais cov PCBS sib txawv thiab ua kom ntseeg tau cov ntawv ci tooj liab du rau txheej sab nraud ntawm LUB PCB. Ob sab ntawm PCB tau npog nrog txheej txheej ntawm tooj liab du.

drilling

Yuav ua li cas koj txuas plaub plaub txheej uas tsis kov cov ntawv tooj liab ua ke hauv PCB? PCB yog thawj qhov drilled los ntawm qhov, tom qab ntawd nws yog xim hlau los ua hluav taws xob.

Lub tshuab xoo hluav taws xob siv los nrhiav lub hauv paus ntawm pawg sab hauv. Lub tshuab yuav cia li nrhiav thiab nrhiav qhov chaw nyob ntawm lub rooj tsavxwm, thiab tom qab ntawd ua qhov chaw rau PCB kom ntseeg tau tias cov hauv qab no yog los ntawm qhov chaw ntawm txoj haujlwm.

Place a sheet of aluminum on the punch machine and then place the PCB on top. Raws li kev khawb av yog txheej txheem qeeb, txhawm rau txhim kho kev ua tau zoo, 1 txog 3 qhov zoo tib yam PCB cov laug cam yuav sib sau ua ke rau qhov tawg raws li tus lej ntawm PCB txheej. Thaum kawg, sab saum toj PCB tau npog nrog txheej txheej txhuas, txheej txheej saum toj thiab hauv qab ntawm txhuas kom thaum lub laum laum tawm hauv thiab tawm, cov ntawv tooj liab ntawm PCB yuav tsis tawg.

The operator then only needs to select the correct drilling procedure and the drilling machine does the rest automatically. Lub laum me ntsis tau tsav los ntawm huab cua siab, nrog qhov siab tshaj plaws ntawm 150,000 kev hloov pauv ib feeb twg, uas yog qhov siab txaus kom ntseeg tau tias lub qhov ntsa du.

Kev hloov pauv ntawm lub laum kuj tseem ua tiav los ntawm lub tshuab raws li txoj haujlwm. The smallest drill can be 100 microns in diameter, while a human hair is 150 microns in diameter.

Hauv cov txheej txheem txheej txheej yav dhau los, cov epoxy yaj tau raug extruded rau sab nraud ntawm PCB, yog li nws yuav tsum tau muab tshem tawm. Lub tshuab milling tuag txiav ib puag ncig ntawm PCB raws li XY kev ua haujlwm raug.

Tshuaj nag los ntawm tooj liab ntawm phab ntsa pore

Txij li yuav luag txhua qhov PCB tsim siv perforations los txuas ntau txheej ntawm kab, kev sib txuas zoo yuav tsum muaj 25 micron tooj liab zaj duab xis ntawm lub qhov ntsa. This thickness of copper film is achieved by electroplating, but the hole wall is made of non-conductive epoxy resin and fiberglass board. Yog li ntawd, thawj kauj ruam yog txhawm rau txhawm rau txheej txheej cov khoom siv ntawm lub qhov phab ntsa, thiab tsim 1-micron tooj liab zaj duab xis ntawm tag nrho PCB nto, suav nrog lub qhov phab ntsa, los ntawm kev tso tshuaj. Tag nrho cov txheej txheem, xws li kev kho tshuaj thiab ntxuav, yog tswj los ntawm cov tshuab.

Tsau PCB

Ntxuav PCB

Delivery of PCB

Chemical precipitation of copper film

Transfer the layout of the outer PCB

Next, the layout of the outer PCB will be transferred to the copper foil. The process is similar to that of the PCB layout of the inner core board, which is transferred to the copper foil using photocopied film and photosensitive film. The only difference is that the positive plate will be used as the board.

The transfer of inner PCB layout introduced above adopts the subtraction method and adopts the negative plate as the board. PCB covered by solidified photosensitive film is circuit, clean the unsolidified photosensitive film, exposed copper foil is etched, PCB layout circuit is protected by solidified photosensitive film. The outer PCB layout is transferred by the normal method, and the positive plate is used as the board. The area covered by a cured film on a PCB is a non – line area. After cleaning the uncured film, electroplating is carried out. Yog tsis muaj zaj duab xis tuaj yeem ua hluav taws xob, thiab tsis muaj zaj duab xis, thawj tooj liab thiab tom qab ntawd plating. Tom qab cov yeeb yaj kiab raug tshem tawm, alkaline etching tau nqa tawm, thiab thaum kawg tin tau raug tshem tawm. The circuit pattern is left on the board because it is protected by tin.

Clean both sides of the copper foil PCB into the press, the press will be sensitive to the copper foil mold pressing.

Txhim kho PCB txheej txheem zaj duab xis ntawm txheej txheej sab saud thiab qis dua los ntawm qhov chaw tso, thiab muab PCB pawg thawj coj los nyob hauv nruab nrab. The photosensitive film under the transmittance film is then solidified by UV lamp irradiation, which is the line that needs to be preserved.

After cleaning the film that is not needed and has not been cured, inspect it.

Clamp PCB thiab electroplate tooj liab. Raws li tau hais ua ntej, txhawm rau kom ntseeg tau tias lub qhov muaj cov hluav taws xob ua tau zoo, zaj duab xis tooj liab electroplated ntawm lub qhov phab ntsa yuav tsum muaj qhov tuab ntawm 25 microns, yog li tag nrho cov kab ke yuav raug tswj los ntawm lub computer kom ntseeg tau tias nws raug.

Tsau PCB

Khoos phis tawj tswj hwm thiab electroplating tooj liab

Tom qab cov yeeb yaj kiab tooj liab tau electroplated, lub khoos phis tawj npaj rau txheej nyias ntawm cov tin kom rov ua dua.

Tom qab tshem tawm cov tin plated PCB board, xyuas kom ntseeg tau tias cov tuab ntawm tooj liab thiab tin plating raug.

Txheej sab nrauv PCB

Tom ntej no, kev ua tiav cov kab sib dhos ua tiav tiav ua tiav txheej txheem. Ua ntej tshaj, ntxuav tawm zaj duab xis kho ntawm PCB pawg thawj coj.

Lub alkali muaj zog yog tom qab ntawd siv los ntxuav tawm cov ntawv tsis xav tau tooj liab uas tau npog los ntawm nws.

Tom qab ntawd cov txheej txheem tin ntawm cov ntawv ci tooj liab ntawm PCB txheej txheem raug tshem tawm nrog cov tshuaj txau tshem tawm. After cleaning, 4 layers PCB layout is completed.