1 Daim ntawv thov ntawm laser beam

Lub siab ceev PCB pawg thawj coj saib yog ib txheej txheej ntau, uas yog sib cais los ntawm insulating resin tov nrog iav fiber ntau cov ntaub ntawv, thiab ib tug conductive txheej ntawm tooj liab ntawv ci yog muab tso rau ntawm lawv. Tom qab ntawd nws yog laminated thiab sib koom ua ke. Daim duab 1 qhia ib ntu ntawm 4-txheej board. Lub hauv paus ntsiab lus ntawm kev ua laser yog siv laser beams tsom rau ntawm qhov chaw ntawm PCB kom yaj tam sim ntawd thiab vaporize cov khoom los ua qhov me me. Txij li tooj liab thiab resin yog ob yam khoom sib txawv, qhov kub ntawm cov ntawv ci tooj liab yog 1084 ° C, thaum lub melting kub ntawm insulating resin tsuas yog 200-300 ° C. Yog li ntawd, nws yog ib qho tsim nyog yuav tsum xaiv thiab raug tswj tsis tau xws li beam wavelength, hom, txoj kab uas hla, thiab mem tes thaum siv laser drilling.

1.1 Kev cuam tshuam ntawm nqaj wavelength thiab hom ntawm kev ua

Dab tsi yog daim ntawv thov ntawm laser ua nyob rau hauv high-density PCB manufacturing

Daim duab 1 Hla-sectional saib ntawm 4-txheej PCB

Nws tuaj yeem pom los ntawm daim duab 1 tias lub laser yog thawj zaug ua cov ntawv ci tooj liab thaum perforating, thiab qhov nqus ntawm tooj liab mus rau laser nce nrog qhov nce ntawm lub wavelength. YAG / UV laser nqus ntawm 351 txog 355 m yog siab li 70%. YAG/UV laser los yog conformal daim npog qhov ncauj txoj kev yuav siv tau los perforate zoo tib yam luam boards. Txhawm rau kom muaj kev sib koom ua ke ntawm high-density PCB, txhua txheej ntawm cov ntawv ci tooj liab tsuas yog 18μm, thiab cov resin substrate nyob rau hauv cov ntawv ci tooj liab muaj qhov nqus siab ntawm carbon dioxide laser (kwv yees li 82%), uas muab cov kev mob rau daim ntawv thov. carbon dioxide laser perforation. Vim tias qhov kev hloov pauv ntawm cov duab hluav taws xob thiab kev ua haujlwm ntawm carbon dioxide laser ntau dua li ntawm YAG / UV laser, tsuav yog muaj lub teeb txaus txaus thiab cov ntawv ci tooj liab tau ua tiav txhawm rau nce nws qhov nqus ntawm laser, carbon dioxide laser. tuaj yeem siv ncaj qha qhib PCB.

Lub transverse hom hom ntawm lub laser beam muaj kev cuam tshuam zoo rau lub divergence lub kaum sab xis thiab lub zog tso zis ntawm lub laser. Txhawm rau kom tau txais cov kab hluav taws xob txaus, nws yog ib qho tsim nyog yuav tsum muaj cov kab teeb pom kev zoo. Lub xeev zoo tshaj plaws yog los tsim ib qho kev txiav txim qis Gaussian hom tso zis raws li pom nyob rau hauv daim duab 2. Nyob rau hauv no txoj kev, ib tug siab zog ceev yuav tau, uas muab ib tug prerequisite rau lub beam kom zoo teem rau lub lens.

Dab tsi yog daim ntawv thov ntawm laser ua nyob rau hauv high-density PCB manufacturing

Daim duab 2 Tus nqi qis Gaussian hom hluav taws xob faib

Hom kev txiav txim qis tuaj yeem tau txais los ntawm kev hloov kho qhov tsis sib xws ntawm lub resonator lossis txhim kho lub diaphragm. Txawm hais tias qhov kev teeb tsa ntawm lub diaphragm txo qhov tso zis ntawm lub zog ntawm lub zog, nws tuaj yeem txwv qhov kev txiav txim siab hom laser los koom rau hauv perforation thiab pab txhim kho lub roundness ntawm lub qhov me me. .

1.2 Tau txais micropores

Tom qab lub wavelength thiab hom ntawm cov nqaj raug xaiv, thiaj li yuav tau txais ib qho zoo tagnrho qhov ntawm PCB, txoj kab uas hla ntawm qhov chaw yuav tsum tau tswj. Tsuas yog tias txoj kab uas hla ntawm qhov chaw me me txaus, lub zog tuaj yeem mloog zoo rau ablating lub phaj. Muaj ntau ntau txoj hauv kev los kho qhov chaw txoj kab uas hla, feem ntau yog los ntawm lub ntsej muag kheej kheej tsom. Thaum Gaussian hom beam nkag mus rau hauv lub lens, qhov chaw txoj kab uas hla ntawm lub nraub qaum focal dav hlau ntawm lub lens tuaj yeem kwv yees kwv yees nrog cov qauv hauv qab no:

D≈λF/(πd)

Nyob rau hauv tus qauv: F yog lub focal ntev; d yog qhov chaw vojvoog ntawm Gaussian beam projected los ntawm ib tug neeg ntawm lub lens nto; λ yog laser wavelength.

Nws tuaj yeem pom los ntawm cov qauv uas qhov loj dua qhov xwm txheej txoj kab uas hla, qhov me me ntawm qhov chaw tsom. Thaum lwm yam xwm txheej tau lees paub, ua kom luv luv ntawm qhov focal ntev yog qhov tsim nyog los txo cov kab teeb. Txawm li cas los xij, tom qab F luv luv, qhov kev ncua deb ntawm lub lens thiab lub workpiece kuj raug txo. Lub slag yuav txaws rau ntawm qhov chaw ntawm lub lens thaum lub sij hawm drilling, uas yuav cuam tshuam rau cov nyhuv drilling thiab lub neej ntawm lub lens. Hauv qhov no, cov cuab yeej pabcuam tuaj yeem ntsia tau rau sab ntawm lub lens thiab siv roj. Ua kom huv si.

1.3 Kev cuam tshuam ntawm beam mem tes

Ib tug multi-pulse laser yog siv rau drilling, thiab lub hwj chim ceev ntawm lub mem tes laser yuav tsum tau tsawg kawg yog mus txog rau lub evaporation kub ntawm daim ntawv tooj liab. Vim hais tias lub zog ntawm ib leeg-mem tes laser tau tsis muaj zog tom qab hlawv los ntawm cov ntawv ci tooj liab, lub hauv paus substrate tsis tuaj yeem ua tau zoo, thiab qhov xwm txheej tau tshwm sim hauv daim duab 3a yuav raug tsim, kom lub qhov ntawm lub qhov tsis tuaj yeem tsim. Txawm li cas los xij, lub zog ntawm cov nqaj yuav tsum tsis txhob siab dhau thaum xuas nrig ntaus, thiab lub zog siab dhau lawm. Tom qab cov ntawv ci tooj liab nkag mus, qhov ablation ntawm lub substrate yuav loj dhau, uas ua rau muaj qhov xwm txheej tshwm sim hauv daim duab 3b, uas tsis zoo rau kev ua haujlwm tom qab ntawm lub rooj tsav xwm Circuit Court. Nws yog qhov zoo tshaj plaws los tsim cov micro-qhov nrog me ntsis tapered qhov qauv raws li qhia hauv daim duab 3c. Qhov qauv no tuaj yeem muab kev yooj yim rau cov txheej txheem tooj liab-plating tom ntej.

Dab tsi yog daim ntawv thov ntawm laser ua nyob rau hauv high-density PCB manufacturing

Daim duab 3 Qhov hom ua tiav los ntawm ntau lub zog lasers

Txhawm rau kom ua tiav lub qhov qauv qhia hauv daim duab 3c, siv lub tshuab nqus laser nrog lub ncov pem hauv ntej (Daim duab 4). Lub zog pulse ntau dua nyob rau hauv pem hauv ntej kawg tuaj yeem ua rau cov ntawv ci tooj liab, thiab ntau lub pulses nrog qis zog nyob rau tom qab kawg tuaj yeem ablate lub insulating substrate thiab ua rau lub qhov tob kom txog rau thaum cov ntawv nyiaj qis dua.

Dab tsi yog daim ntawv thov ntawm laser ua nyob rau hauv high-density PCB manufacturing

Daim duab 4 Pulse laser waveform

2 Laser beam effect

Vim hais tias cov khoom siv ntawm cov ntawv ci tooj liab thiab cov substrate sib txawv heev, cov khoom siv laser thiab cov khoom siv hluav taws xob sib cuam tshuam los tsim ntau yam cuam tshuam, uas muaj qhov cuam tshuam tseem ceeb ntawm qhov aperture, qhov tob, thiab qhov ntawm lub micropores.

2.1 Reflection thiab nqus ntawm laser

Kev sib cuam tshuam ntawm lub laser thiab PCB thawj zaug pib los ntawm qhov teeb meem laser raug cuam tshuam thiab nqus los ntawm cov ntawv ci tooj liab ntawm qhov chaw. Vim tias cov ntawv ci tooj liab muaj qhov nqus tsawg heev ntawm infrared wavelength carbon dioxide laser, nws nyuaj rau kev ua haujlwm thiab kev ua haujlwm tsawg heev. Qhov absorbed ib feem ntawm lub teeb lub zog yuav ua rau kom cov dawb electron kinetic zog ntawm cov khoom siv tooj liab, thiab feem ntau ntawm nws yuav hloov mus rau hauv lub zog kub ntawm cov ntawv ci tooj liab los ntawm kev sib cuam tshuam ntawm electrons thiab siv lead ua lattices lossis ions. Qhov no qhia tau hais tias thaum txhim kho cov nqaj zoo, nws yog ib qho tsim nyog yuav tsum tau ua ntej kev kho mob ntawm cov ntawv ci tooj liab. Qhov saum npoo ntawm cov ntawv ci tooj liab tuaj yeem coated nrog cov ntaub ntawv uas ua rau kom lub teeb nqus kom nce nws qhov nqus ntawm lub teeb laser.

2.2 Lub luag haujlwm ntawm beam effect

Thaum lub sij hawm laser ua, lub teeb beam radiates cov khoom siv tooj liab, thiab cov ntawv ci tooj liab yog rhuab mus rau vaporization, thiab chav kub kub yog siab, uas yog ib qho yooj yim rau tawg thiab ionize, uas yog, cov duab induced plasma yog generated los ntawm lub teeb excitation. . Lub photo-induced plasma feem ntau yog plasma ntawm cov khoom vapor. Yog hais tias lub zog xa mus rau lub workpiece los ntawm lub plasma yog ntau tshaj qhov poob ntawm lub teeb lub zog uas tau txais los ntawm lub workpiece los ntawm kev nqus ntawm cov ntshav. Lub plasma hloov kho qhov nqus ntawm lub zog laser los ntawm lub workpiece. Txwv tsis pub, lub plasma thaiv lub laser thiab tsis muaj zog nqus ntawm lub laser los ntawm lub workpiece. Rau cov pa roj carbon dioxide lasers, yees duab-induced plasma tuaj yeem ua rau kom tus nqi nqus ntawm cov ntawv ci tooj liab. Txawm li cas los xij, plasma ntau dhau yuav ua rau lub teeb pom kev zoo thaum hla dhau, uas yuav cuam tshuam rau qhov chaw qhov tseeb ntawm lub qhov. Feem ntau, laser fais fab tuag yog tswj tau raws li tus nqi tsim nyog hauv qab 107 W / cm2, uas tuaj yeem tswj tau cov ntshav zoo dua.

Cov nyhuv pinhole plays lub luag haujlwm tseem ceeb hauv kev txhim kho qhov nqus ntawm lub teeb lub zog hauv cov txheej txheem laser drilling. Lub laser txuas ntxiv ablate lub substrate tom qab hlawv los ntawm cov ntawv ci tooj liab. Lub substrate tuaj yeem nqus tau ntau lub teeb lub zog, ua rau vaporizes thiab nthuav dav, thiab lub siab tsim tawm tuaj yeem yog cov khoom molten pov tseg los ua qhov me me. Lub qhov me me kuj tseem muaj cov duab thaij duab plasma, thiab lub zog laser nkag mus rau hauv lub qhov me me tuaj yeem yuav luag tag nrho los ntawm ntau qhov kev xav ntawm lub qhov phab ntsa thiab qhov kev txiav txim ntawm cov ntshav (Daim duab 5). Vim yog kev nqus ntshav plasma, lub zog laser lub zog dhau los ntawm lub qhov me me mus rau hauv qab ntawm lub qhov me me yuav txo qis, thiab lub zog laser lub zog nyob rau hauv qab ntawm lub qhov me me yog qhov tseem ceeb los tsim kom muaj qee qhov vaporization siab kom muaj qee qhov tob ntawm qhov me me, uas txiav txim siab qhov tob tob ntawm cov txheej txheem machining.

Dab tsi yog daim ntawv thov ntawm laser ua nyob rau hauv high-density PCB manufacturing

Daim duab 5 Laser refraction nyob rau hauv lub qhov

3 Xaus

Daim ntawv thov ntawm laser ua tshuab tuaj yeem txhim kho qhov kev ua haujlwm zoo ntawm cov khoom siv high-density PCB micro-qhov. Cov kev sim qhia tias: ① Ua ke nrog cov lej tswj kev siv tshuab, ntau dua 30,000 micro-qhov tuaj yeem ua tiav ib feeb ntawm cov ntawv luam tawm, thiab qhov aperture yog nyob nruab nrab ntawm 75 thiab 100; ② Daim ntawv thov ntawm UV laser tuaj yeem ua rau qhov aperture tsawg dua 50μm lossis me dua, uas tsim cov xwm txheej rau kev nthuav dav ntxiv ntawm qhov chaw siv ntawm PCB boards.