Hauv kev tsim cov txheej txheem PCB, cov txheej txheem kho saum npoo yog ib kauj ruam tseem ceeb heev. Nws tsis tsuas yog cuam tshuam rau cov tsos ntawm PCB, tab sis kuj tseem cuam tshuam ncaj qha rau kev ua haujlwm, kev ntseeg tau thiab kav ntev ntawm PCB. Cov txheej txheem kho saum npoo tuaj yeem muab cov txheej txheem tiv thaiv kom tsis txhob muaj tooj liab corrosion, txhim khu kev ua haujlwm zoo, thiab muab cov khoom siv hluav taws xob zoo. Cov hauv qab no yog ib qho kev soj ntsuam ntawm ntau yam txheej txheem kho qhov chaw hauv PCB ntau lawm.
一.HASL (Hom Cua Smoothing)
Huab cua kub planarization (HASL) yog ib txwm siv PCB nto kho tshuab uas ua haujlwm los ntawm dipping PCB rau hauv molten tin / txhuas alloy thiab tom qab ntawd siv cua kub los "planarize" saum npoo los tsim cov xim hlau tsis sib xws. Cov txheej txheem HASL yog tus nqi qis thiab tsim nyog rau ntau yam ntawm PCB kev tsim khoom, tab sis tej zaum yuav muaj teeb meem nrog cov ntaub qhwv tsis sib xws thiab cov hlau tsis sib xws.
二.ENIG (chemical nickel kub)
Electroless npib tsib xee kub (ENIG) yog txheej txheem uas tso cov npib tsib xee thiab kub txheej rau saum npoo ntawm PCB. Ua ntej, tooj liab nto yog ntxuav thiab qhib, ces ib txheej nyias ntawm cov npib tsib xee tso los ntawm cov tshuaj hloov tshuaj, thiab thaum kawg ib txheej kub yog plated nyob rau sab saum toj ntawm cov nickel txheej. Cov txheej txheem ENIG muab kev tiv thaiv zoo thiab hnav tsis kam thiab tsim nyog rau cov ntawv thov uas muaj kev ntseeg siab, tab sis tus nqi kuj siab.
︉ 、 tshuaj kub
Chemical Gold tso ib txheej nyias ntawm kub ncaj qha rau ntawm PCB nto. Cov txheej txheem no feem ntau yog siv rau hauv daim ntawv thov uas tsis tas yuav tsum tau soldering, xws li xov tooj cua zaus (RF) thiab microwave circuits, vim hais tias kub muab zoo heev conductivity thiab corrosion kuj. Cov tshuaj kub raug nqi tsawg dua ENIG, tab sis tsis yog hnav-resistant li ENIG.
四 、 OSP (organic tiv thaiv zaj duab xis)
Organic tiv thaiv zaj duab xis (OSP) yog txheej txheem uas tsim cov ntaub ntawv nyias nyias ntawm cov tooj liab kom tiv thaiv tooj liab los ntawm oxidizing. OSP muaj cov txheej txheem yooj yim thiab tus nqi qis, tab sis kev tiv thaiv nws muab yog qhov tsis muaj zog thiab tsim nyog rau lub sijhawm luv luv thiab siv PCBs.
五、Hard kub
Hard Kub yog txheej txheem uas tso cov txheej kub tuab ntawm PCB nto los ntawm electroplating. Hard kub yog hnav-resistant ntau dua tshuaj kub thiab yog haum rau connectors uas yuav tsum tau nquag ntsaws thiab unplugging los yog PCBs siv nyob rau hauv hnyav ib puag ncig. Cov kub kub raug nqi ntau dua li cov tshuaj kub tab sis muab kev tiv thaiv zoo dua mus ntev.
六, Immersion Silver
Immersion Silver yog txheej txheem rau tso nyiaj txheej txheej ntawm PCB. Silver muaj zoo conductivity thiab reflectivity, ua rau nws haum rau pom thiab infrared daim ntaub ntawv. Tus nqi ntawm cov txheej txheem immersion nyiaj yog nruab nrab, tab sis cov nyiaj txheej yog yooj yim vulcanized thiab xav tau kev tiv thaiv ntxiv.
Nyob rau hauv tas li ntawd mus rau lub Immersion Tin
Immersion Tin yog txheej txheem rau tso cov tin txheej rau ntawm qhov chaw ntawm PCB. Lub tin txheej muab zoo soldering zog thiab ib co corrosion kuj. Cov txheej txheem immersion tin yog pheej yig dua, tab sis cov txheej tin tau yooj yim oxidized thiab feem ntau yuav tsum muaj txheej txheej tiv thaiv ntxiv.
八, Lead-Free HASL
Lead-Free HASL yog RoHS-raws li HASL txheej txheem uas siv lead-free tin / silver / tooj liab alloy los hloov cov tsoos tin / txhuas alloy. Cov txheej txheem HASL tsis muaj txhuas muab kev ua haujlwm zoo ib yam li HASL ib txwm muaj tab sis ua tau raws li qhov xav tau ntawm ib puag ncig.
Muaj ntau yam txheej txheem kho deg hauv PCB ntau lawm, thiab txhua txoj kev muaj nws qhov tshwj xeeb zoo thiab daim ntawv thov scenarios. Kev xaiv cov txheej txheem kho kom haum rau saum npoo yuav tsum xav txog qhov kev thov ib puag ncig, kev xav tau ntawm kev ua haujlwm, kev siv nyiaj txiag thiab kev tiv thaiv ib puag ncig ntawm PCB. Nrog txoj kev loj hlob ntawm cov cuab yeej siv hluav taws xob, cov txheej txheem kho saum npoo tshiab tau tshwm sim ntxiv, muab cov tuam txhab PCB nrog ntau txoj kev xaiv kom tau raws li kev hloov pauv kev lag luam.