PTH txheej txheem hauv PCB tsim

Electroless tooj liab plating, tseem hu ua plated los ntawm qhov (PTH), yog tus kheej-catalyzed redox cov tshuaj tiv thaiv. Cov txheej txheem PTH yog ua tom qab drilling ob lossis ntau txheej.

Kev ua haujlwm ntawm PTH: Ntawm qhov drilled non-conductive cell phab ntsa substrate, nyias txheej ntawm electroless tooj liab yog electroless deposited raws li ib tug substrate rau tom ntej electroplating tooj liab.

Decomposition ntawm PTH txheej txheem: alkaline degreasing → 2 lossis 3 countercurrent rinses → roughening (micro-etching) → Secondary countercurrent rinse → pre-dip → activation → Secondary countercurrent rinse → debonding → Secondary countercurrent rinse → sinking → two Level countercurrent flush.

PTH piav qhia txog txheej txheem txheej txheem:

1. Alkaline degreasing:

Tshem tawm cov roj, cov ntiv tes, oxides, plua plav hauv lub qhov ntawm lub rooj tsavxwm;

Kho qhov kev them nyiaj ntawm lub pore phab ntsa los ntawm qhov tsis zoo mus rau qhov zoo los txhawb cov adsorption ntawm colloidal palladium hauv cov txheej txheem tom ntej;

Tom qab degreasing, nws yuav tsum tau ntxuav nruj me ntsis raws li cov lus qhia thiab yuav tsum tau sim nrog tooj liab backlight test

2. micro etching

Tshem tawm oxide ntawm lub rooj tsavxwm thiab roughen qhov chaw kom ntseeg tau tias zoo adhesion ntawm cov tooj liab txheej tom ntej mus rau tooj liab nyob rau hauv qab ntawm lub substrate.

Tus tshiab tooj liab nto muaj zog ua hauj lwm thiab muaj peev xwm adsorb colloidal palladium zoo;

3. pre-impregnated

Nws tsuas yog tiv thaiv lub palladium tank los ntawm cov pa phem ntawm pretreatment tank thiab prolongs lub neej kev pab cuam ntawm lub palladium tank. Tsuas yog palladium chloride, cov khoom tseem ceeb yog tib yam li lub tank palladium, palladium chloride tuaj yeem ntub cov phab ntsa pore zoo, thiab txhawb cov kev ua haujlwm tom ntej ntawm kev ua kom muaj kuab paug. ua kom txaus txaus;

4. kev ua haujlwm

Pretreatment Tom qab alkaline degreasing thiab polarity hloov, cov phab ntsa pore zoo tuaj yeem ua rau cov khoom tsis zoo ntawm colloidal palladium hais, kom ntseeg tau qhov nruab nrab tom qab, txuas ntxiv thiab ntom ntom ntawm tooj liab; Kev ua kom muaj zog yog qhov tseem ceeb rau qhov zoo ntawm cov da dej tooj liab tom ntej. Cov ntsiab lus tswj: lub sijhawm teev; tus qauv stannous ion thiab chloride ion concentration; tshwj xeeb lub ntiajteb txawj nqus, acidity thiab kub kuj tseem ceeb, thiab yuav tsum tau tswj nruj me ntsis raws li cov lus qhia kev khiav hauj lwm.

5. Peptidation

Lub stannous ions ntawm lub colloidal palladium hais raug tshem tawm, thiab palladium nuclei nyob rau hauv cov colloidal hais yog raug mus ncaj qha catalyze qhov pib ntawm cov tshuaj tooj liab nag lossis daus cov tshuaj tiv thaiv. Kev paub dhau los tau pom tias kev siv fluorobic acid ua tus neeg sawv cev debonding yog qhov kev xaiv zoo dua.

6. Electroless tooj liab plating

Cov tshuaj tiv thaiv tus kheej ntawm electroless tooj liab plating yog tshwm sim los ntawm kev ua kom lub palladium nucleus, thiab ob qho tib si cov tshuaj tooj liab tshiab thiab cov tshuaj tiv thaiv los ntawm cov khoom siv hydrogen tuaj yeem siv los ua cov tshuaj tiv thaiv catalysts rau cov tshuaj tiv thaiv catalytic, tso cai rau cov nag lossis daus ntawm tooj liab mus txuas ntxiv. . Tom qab cov kauj ruam no, ib txheej ntawm electroless tooj liab tuaj yeem tso rau ntawm qhov chaw ntawm lub phaj lossis ntawm phab ntsa ntawm lub qhov. Thaum lub sij hawm tus txheej txheem no, lub da dej yuav tsum tau khaws cia nyob rau hauv ib txwm huab cua agitation los hloov ntau soluble divalent tooj liab.

Qhov zoo ntawm cov txheej txheem tooj liab plating yog ncaj qha ntsig txog qhov zoo ntawm cov khoom siv hluav taws xob tsim hluav taws xob. Nws yog lub hauv paus txheej txheem ntawm vias thiab luv. Kev kuaj pom pom tsis yooj yim. Postprocessing tsuas yog siv rau kev soj ntsuam qhov tshwm sim los ntawm kev sim ua kom puas tsuaj. Tshawb xyuas zoo thiab saib xyuas ib lub rooj tsavxwm PCB. Thaum muaj teeb meem tshwm sim, yuav muaj teeb meem batch inevitably. Txawm hais tias qhov kev xeem tsis tuaj yeem ua tiav, cov khoom kawg yuav ua rau muaj kev phom sij zoo thiab tsuas tuaj yeem muab pov tseg hauv cov khoom siv, yog li ua raws li cov lus qhia ua haujlwm nruj me ntsis.