Lub laser yog lub teeb muaj zog ntawm lub teeb uas zoo siab thaum lub "duab tshav" txhawb nqa los ntawm kev txhawb nqa sab nraud uas ua rau nws lub zog. Infrared thiab pom lub teeb muaj thermal zog, thaum lub teeb ultraviolet muaj lub zog kho qhov muag. Thaum lub teeb hom no hits nto ntawm lub workpiece, peb phenomena tshwm sim: reflection, absorption thiab nkag mus.
Lub luag haujlwm tseem ceeb ntawm laser drilling yog tuaj yeem tshem tawm cov khoom siv substrate sai sai, feem ntau yog los ntawm photothermal ablation thiab photochemical ablation lossis hu ua excision.
- Diam duab-thermal ablation: Lub hauv paus ntsiab lus ntawm lub qhov tsim nyob rau hauv uas cov khoom yuav tsum tau ua absorbs siab zog laser lub teeb, heats mus rau melting nyob rau hauv ib tug luv luv lub sij hawm, thiab yog evaporated. Cov txheej txheem no nyob rau hauv cov khoom siv substrate yog raug rau lub zog siab, nyob rau hauv lub qhov tsim los ntawm phab ntsa ntawm blackened carbonized residue, lub qhov yuav tsum tau ntxuav ua ntej.
- Photochemical ablation: hais txog thaj tsam ultraviolet muaj lub zog photon siab (ntau tshaj 2 eV electron volt), laser wavelength ntawm ntau tshaj 400 nanometers ntawm high-zog photons ua lub luag haujlwm hauv cov txiaj ntsig. Qhov no high-zog photons tuaj yeem rhuav tshem cov saw ntev molecular ntawm cov khoom siv organic, ua cov khoom me me, thiab nws lub zog yog ntau dua li cov khoom qub molecules, lub zog loj heev los ntawm kev khiav tawm, nyob rau hauv cov ntaub ntawv ntawm sab nraud pinch suction, kom cov khoom siv substrate. yog sai sai tshem tawm thiab tsim ntawm microporous. Hom txheej txheem no tsis muaj thermal hlawv thiab tsis tsim carbonization. Yog li ntawd, nws yooj yim heev los ntxuav ua ntej poration. Cov no yog cov hauv paus ntsiab lus ntawm kev tsim lub qhov laser. Tam sim no feem ntau siv ob hom laser drilling: luam ntawv Circuit Court board drilling nrog lasers yog tsuas yog RF-excited CO2 roj lasers thiab UV solid-state Nd: YAG lasers.
- Ntawm lub substrate absorbance: qhov ua tau zoo ntawm lub laser muaj kev sib raug zoo nrog cov absorbance ntawm cov khoom siv substrate. Cov ntawv luam tawm cov ntawv luam tawm yog ua los ntawm cov ntawv ci tooj liab thiab cov ntaub iav thiab cov khoom siv sib xyaw ua ke, qhov nqus ntawm peb cov ntaub ntawv no kuj sib txawv vim muaj qhov sib txawv ntawm cov wavelengths, tab sis cov ntawv ci tooj liab thiab iav ntaub hauv ultraviolet 0.3mμ hauv qab cheeb tsam ntawm qhov nqus tau siab dua, tab sis mus rau hauv qhov pom kev pom thiab IR tom qab poob ntau heev. Organic resin cov ntaub ntawv, ntawm qhov tod tes, tuaj yeem tswj tau qhov nqus tau zoo nyob rau hauv tag nrho peb spectral bands. Qhov no yog cov yam ntxwv uas cov ntaub ntawv cob muaj thiab yog lub hauv paus rau qhov nrov ntawm cov txheej txheem laser drilling.
Dab tsi ntawm laser drilling muaj nyob rau hauv PCB factories?
Lub laser yog ib lub teeb muaj zog ntawm lub teeb uas zoo siab heev thaum "rays" raug txhawb los ntawm kev txhawb nqa sab nraud uas ua rau nws lub zog nce ntxiv, nrog lub teeb pom kev zoo thiab pom lub teeb muaj thermal zog thiab ultraviolet lub teeb muaj lub zog kho qhov muag. Thaum lub teeb hom no hits nto ntawm lub workpiece, peb phenomena tshwm sim: reflection, absorption thiab nkag mus. Lub luag haujlwm tseem ceeb ntawm laser drilling yog tuaj yeem tshem tawm cov khoom siv substrate sai sai, uas feem ntau yog los ntawm photothermal ablation thiab photochemical ablation los yog hu ua excision.
Ob lub laser technologies yog siv rau laser drilling hauv kev lag luam PCB ntau lawm: CO2 lasers nrog wavelengths nyob rau hauv lub far-infrared band, thiab UV lasers nrog wavelengths nyob rau hauv lub ultraviolet band.CO2 lasers yog dav siv nyob rau hauv zus tau tej cov micropass qhov nyob rau hauv luam Circuit Court boards. , uas yuav tsum muaj txoj kab uas hla ntau dua 100 μm (Raman, 2001). Rau kev tsim cov qhov loj ntawm qhov aperture, CO2 lasers yog cov khoom tsim tau zoo vim lub sijhawm luv luv uas yuav tsum tau muaj rau kev tsim cov apertures loj nrog CO2 lasers. UV laser tshuab yog dav siv nyob rau hauv fabrication ntawm microvias nrog diameters ntawm tsawg tshaj li 100 μm, thiab txawm tsawg tshaj li 50 μm nrog kev siv ntawm microfabricated thaiv daim duab. UV laser tshuab ua haujlwm zoo heev hauv kev tsim cov qhov nrog txoj kab uas hla tsawg dua 80 μm. Yog li ntawd, kom ua tau raws li qhov kev thov ntau ntxiv rau microvia tsim tau, ntau lub tuam txhab PCB tau pib ua kom paub lub taub hau ob lub laser drilling tshuab.
Cov hauv qab no yog peb hom tseem ceeb ntawm dual lub taub hau laser drilling tshuab muaj nyob rau hauv kev ua lag luam niaj hnub no:
- Dual-head UV laser drilling tshuab
- Dual lub taub hau CO2 laser drilling tshuab; thiab
- Stick laser drilling tshuab (CO2 thiab UV)
Tag nrho cov hom drilling tshuab muaj lawv tus kheej zoo thiab qhov tsis zoo. Laser drilling tshuab tuaj yeem yooj yim muab faib ua ob hom, dual laum ib lub wavelength systems thiab dual laum dual wavelength systems.
Txawm li cas los xij, muaj ob lub ntsiab lus tseem ceeb uas cuam tshuam rau lub peev xwm los laum qhov:
- Lub zog laser / mem tes zog
- Lub beam positioning system
Lub zog ntawm lub laser mem tes thiab qhov ua tau zoo ntawm cov nqaj xa khoom txiav txim siab lub sijhawm drilling, lub sijhawm drilling yog lub sijhawm nws yuav siv lub tshuab laser laum rau lub qhov micropass, thiab lub nqaj tso qhov system txiav txim siab qhov ceev ntawm qhov nws tuaj yeem txav mus los ntawm ob. qhov. Ua ke, cov xwm txheej no txiav txim siab qhov ceev ntawm lub tshuab laser drilling tuaj yeem tsim cov microvias xav tau rau qhov yuav tsum tau ua. Dual-lub taub hau UV laser tshuab yog qhov zoo tshaj plaws rau qhov drilling qhov me dua 90μm hauv kev sib xyaw ua ke nrog qhov sib piv siab.
Lub dual-head CO2 laser system siv Q-modulated RF-excited CO2 laser. Qhov zoo ntawm cov kab ke no yog qhov ua tau zoo dua qub (txog 100 kHz), lub sijhawm luv luv drilling, thiab qhov chaw ua haujlwm dav, uas tso cai rau lub qhov muag tsis pom drilled nrog ob peb qhov dhau los, tab sis qhov zoo ntawm qhov drilled tuaj yeem ua tau. qis.
Qhov feem ntau dual-lub taub hau laser drilling system yog hybrid laser drilling system, uas muaj UV laser taub hau thiab lub taub hau CO2 laser. Qhov no ua ke hybrid laser drilling txoj kev tso cai rau ib txhij drilling ntawm tooj liab thiab dielectrics. Cov tooj liab yog drilled nrog UV laser los tsim qhov xav tau qhov loj thiab cov duab, thiab CO2 laser yog siv los laum lub uncovered dielectric tam sim ntawd tom qab ntawd. Cov txheej txheem drilling yog ua tiav los ntawm qhov drilling 2in X 2in thaiv hu ua teb.
Lub CO2 laser zoo tshem tawm cov dielectrics, txawm tias cov iav tsis muaj zog ntxiv dielectrics. Txawm li cas los xij, ib qho CO2 laser tsis tuaj yeem ua qhov me me (tsawg dua 75 μm) thiab tshem tawm cov tooj liab, nrog rau ob peb qhov tshwj xeeb uas nws tuaj yeem tshem tawm cov txheej txheem ua ntej nyias nyias ntawm qhov tsawg dua 5 μm (lustino, 2002). UV laser muaj peev xwm ua qhov me me thiab tshem tawm txhua txoj kev tooj liab (3 - 36 μm, 1oz, txawm plated tooj liab foils). UV laser kuj tseem tuaj yeem tshem tawm cov ntaub ntawv dielectric ib leeg, tab sis ntawm tus nqi qis dua. Ntxiv mus, rau cov ntaub ntawv tsis sib xws, xws li iav FR-4, cov txiaj ntsig feem ntau tsis zoo. Qhov no yog vim hais tias cov iav tsuas yog raug tshem tawm yog tias lub zog ceev yog nce mus rau ib theem, uas tseem ua rau cov ntaub qhwv sab hauv puas. Txij li thaum lub nplaum laser system muaj UV laser thiab CO 2 laser, nws yog qhov zoo tshaj plaws nyob rau hauv ob qho tib si, nrog rau UV laser tag nrho cov tooj liab foils thiab qhov me me tuaj yeem ua tiav, thiab nrog CO 2 laser dielectrics tuaj yeem drilled sai. Daim duab muab ib qho piv txwv ntawm cov qauv ntawm lub taub hau ob lub laser drilling system nrog programmable drilling qhov sib nrug. Qhov sib nrug ntawm ob qhov kev xyaum tuaj yeem hloov kho los ntawm nws tus kheej raws li kev teeb tsa ntawm cov khoom siv, uas ua kom muaj peev xwm ua tau zoo tshaj plaws laser drilling.
Niaj hnub no, qhov sib nrug ntawm ob qhov kev xyaum yog kho nyob rau hauv feem ntau dual-lub taub hau laser drilling tshuab nrog cov kauj ruam-thiab-repeat beam positioning technology. Qhov kom zoo dua ntawm cov kauj ruam-thiab-repeat laser tej thaj chaw deb maub los nws tus kheej yog qhov kev hloov kho loj ntawm cov npe (txog (50 X 50) μm). Qhov tsis zoo yog tias lub laser teleconverter yuav tsum tau nce mus rau qhov chaw ruaj khov thiab qhov sib nrug ntawm ob qhov kev xyaum yog tsau. Qhov kev ncua deb ntawm ob qhov kev xyaum ntawm ib tug raug dual-lub taub hau laser tej thaj chaw deb regulator yog tsau (kwv yees li 150 μm). Rau qhov ntau thiab tsawg ntawm vaj huam sib luag, qhov kev xyaum ua haujlwm ruaj khov tsis tuaj yeem ua kom zoo rau kev ua haujlwm kom tiav nrog rau qhov programmable drills.
Niaj hnub no lub dual-lub taub hau laser drilling tshuab muaj nyob rau hauv ntau qhov ntau thiab tsawg thiab kev ua yeeb yam rau ob qho tib si me me PCB tuam ntxhab thiab rau cov tuam txhab loj PCB.
Ceramic aluminium oxide yog siv rau hauv kev tsim cov ntawv luam tawm Circuit Board vim nws qhov siab dielectric tas li. Txawm li cas los xij, vim nws qhov tsis yooj yim, cov txheej txheem drilling yuav tsum tau siv rau kev xaim thiab kev sib dhos yog qhov nyuaj nrog cov cuab yeej txheem, vim tias kev ntxhov siab yuav tsum tau txo qis, uas yog qhov zoo rau laser drilling.Rangel li al. (1997) pom tau hais tias rau alumina substrates, nrog rau cov alumina substrates coated nrog kub thiab thauj tog rau nkoj, nws muaj peev xwm xyaum siv lub tuned QNd:YAG laser. Kev siv lub tshuab hluav taws xob luv luv, lub zog qis, lub zog siab-npaum-lub zog laser tau pab kom tsis txhob muaj kev puas tsuaj rau cov qauv los ntawm cov neeg kho tshuab kev ntxhov siab thiab tsim cov khoom zoo los ntawm qhov nrog cov diameters tsawg dua 100 μm. Cov thev naus laus zis no tau ua tiav hauv cov suab nrov hauv microwave amplifiers hauv qhov ntau zaus ntawm 8 - 18 GHz.
Nd:YAG laser thev naus laus zis tau siv los ua ob qho tib si qhov muag tsis pom thiab los ntawm qhov hauv ntau yam khoom siv. Ntawm cov no yog qhov drilling ntawm qhov kev sim hauv polyimide copper-clad laminates nrog qhov tsawg kawg nkaus txoj kab uas hla ntawm 25 microns. Kev txheeb xyuas tus nqi tsim khoom, txoj kab uas siv tau tshaj plaws siv yog 25-125 microns. Qhov drilling ceev yog 10,000 qhov/min. Direct laser xuas nrig ntaus txheej txheem yuav siv tau, lub qhov taub txog li 50 microns. Lub puab nto ntawm lub qhov molded yog huv si thiab tsis muaj carbonization thiab yuav ua tau yooj yim plated. Tib yam kuj tuaj yeem ua tau nyob rau hauv PTFE tooj liab-clad laminate drilling los ntawm qhov, qhov tsawg tshaj plaws qhov txoj kab uas hla ntawm 25 microns, lub siab tshaj plaws txoj kab uas hla siv rau 25-125 microns. Drilling ceev yog 4500 qhov / min. Tsis tas yuav tsum tau pre-etching ntawm windows. Cov qhov tshwm sim yog huv si thiab tsis tas yuav tsum tau ua cov txheej txheem tshwj xeeb ntxiv.
