Yuav ua li cas xaiv Surface Finish rau koj tus qauv PCB
Ⅱ Kev ntsuam xyuas thiab kev sib piv
Muaj ntau cov lus qhia txog kev ua kom tiav, xws li HASL tsis muaj txhuas muaj teeb meem kom muaj qhov sib xws.Electrolytic Ni/Au yog qhov kim heev thiab yog tias kub ntau dhau tso rau hauv ncoo, tuaj yeem ua rau cov pob qij txha tawg.Immersion tin muaj solderability degradation tom qab raug mus rau ntau lub tshav kub mus, xws li nyob rau hauv ib tug sab saum toj thiab hauv qab sab PCBA reflow txheej txheem, thiab lwm yam.. Qhov sib txawv ntawm saum npoo finishes yuav tsum tau kom meej meej paub.Cov lus hauv qab no qhia tau hais tias qhov kev ntsuam xyuas ntxhib rau qhov feem ntau siv ua tiav ntawm cov ntawv luam tawm Circuit Board.
Table1 Cov lus piav qhia luv luv ntawm cov txheej txheem tsim khoom, cov txiaj ntsig tseem ceeb thiab qhov tsis zoo, thiab cov ntawv thov raug nyiam ntawm cov hlau lead-dawb nto tiav ntawm PCB
| PCB nto tiav | Txheej txheem | Thickness | Qhov zoo | Qhov tsis zoo | Tej kev siv |
| Lead-free HASL | PCB boards yog immersed nyob rau hauv ib tug molten tin da dej thiab ces tau tshuab los ntawm cov cua kub riam rau tiaj pats thiab tshaj solder tshem tawm. | 30µin (1µm) -1500µin (40µm) | Zoo Solderability;Muaj dav;tuaj yeem kho / rov ua haujlwm dua;Txee ntev ntev | Qhov chaw tsis sib xws;Thermal shock;Kev ntub dej tsis zoo;Solder choj;Txuas PTHs. | Siv dav dav;Haum rau cov ntaub qhwv loj thiab qhov sib txawv;Tsis haum rau HDI nrog <20 mil (0.5mm) zoo suab thiab BGA;Tsis zoo rau PTH;Tsis haum rau tuab tooj liab PCB;Feem ntau, daim ntawv thov: Circuit Court boards rau kev kuaj hluav taws xob, tes soldering, qee cov khoom siv hluav taws xob zoo xws li aerospace thiab tub rog. |
| OSP | Kev siv tshuaj lom neeg cov khoom siv rau cov boards nto tsim cov organic metallic txheej los tiv thaiv cov tooj liab los ntawm xeb. | 46µin (1.15µm) – 52µin (1.3µm) | Tus nqi qis;Pads yog sib xws thiab tiaj tus;Zoo solderability;tuaj yeem ua ke nrog lwm qhov chaw tiav;Txheej txheem yog yooj yim;tuaj yeem rov ua dua (hauv kev cob qhia). | rhiab heev rau kev tuav;Lub neej luv luv.Tsawg heev solder kis;Solderability degradation nrog siab temp & cycles;Nonconductive;Tsis yooj yim rau kev soj ntsuam, ICT sojntsuam, ionic & press-fit kev txhawj xeeb | Siv dav dav;Zoo haum rau SMT / nplua pitches / BGA / me me;Pab pawg thawj coj saib;Tsis zoo rau PTHs;Tsis haum rau crimping technology |
| ENIG | Cov txheej txheem tshuaj lom neeg uas ua rau cov tooj liab nthuav tawm nrog Nickel thiab Kub, yog li nws muaj ob txheej txheej hlau. | 2µin (0.05µm) – 5µin (0.125µm) ntawm kub tshaj 120µin (3µm) – 240µin (6µm) ntawm Nickel | Zoo heev solderability;Cov ntaub qhwv yog tiaj thiab sib xws;Al hlau bendability;Tsawg tiv thaiv;Lub neej txee ntev;Zoo corrosion kuj thiab durability | "Dub Pad" kev txhawj xeeb;Teeb liab poob rau kev siv teeb liab kev ncaj ncees;tsis tuaj yeem rov ua haujlwm dua | Zoo heev rau kev sib dhos ntawm lub suab zoo thiab qhov chaw mount qhov chaw (BGA, QFP ...);Zoo heev rau ntau hom Soldering;Zoo dua rau PTH, nias haum;Hlau Bondable;Pom zoo rau PCB nrog daim ntawv thov kev ntseeg siab xws li aerospace, tub rog, kev kho mob thiab cov neeg siv khoom siab, thiab lwm yam;Tsis pom zoo rau Touch Contact Pads. |
| Electrolytic Ni/Au (Mos kub) | 99.99% ntshiab - 24 carat Kub siv tshaj nickel txheej los ntawm cov txheej txheem electrolytic ua ntej soldermask. | 99.99% Pure kub, 24 Karat 30µin (0.8µm) -50µin (1.3µm) tshaj 100µin (2.5µm) -200µin (5µm) ntawm Nickel | Hard, ruaj nto;Zoo conductivity;Flatness;Al hlau bendability;Tsawg tiv thaiv;Lub neej ntev | kim;Au embrittlement yog tuab heev;layout txwv;Kev ua haujlwm ntxiv / kev ua haujlwm hnyav;Tsis haum rau soldering;Txheej tsis sib xws | Feem ntau yog siv hauv hlau (Al & Au) kev sib txuas hauv cov pob khoom xws li COB (Chip on Board) |
| Electrolytic Ni/Au (Hard kub) | 98% ntshiab - 23 carat Kub nrog hardeners ntxiv rau lub plating da dej thov tshaj nickel txheej los ntawm cov txheej txheem electrolytic. | 98% Ntshiab kub, 23 Karat30µm (0.8µm) -50µin (1.3µm) tshaj 100µin (2.5µm) -150µin (4µm) Nickel | Zoo heev solderability;Cov ntaub qhwv yog tiaj thiab sib xws;Al hlau bendability;Tsawg tiv thaiv;Reworkable | Tarnish (kev tuav & cia) corrosion nyob rau hauv siab sulfur ib puag ncig;Txo cov kev xaiv saw hlau los txhawb qhov kev ua tiav no;Lub qhov rais ua haujlwm luv ntawm cov theem sib dhos. | Feem ntau yog siv rau kev sib txuas hluav taws xob xws li ntug txuas (kub ntiv tes), IC cab kuj boards (PBGA / FCBGA / FCCSP ...), Keyboards, roj teeb hu thiab qee qhov ntsuas ntsuas, thiab lwm yam. |
| Immersion Ag | Ib txheej nyiaj yog tso rau ntawm tooj liab los ntawm cov txheej txheem electroless tom qab etch tab sis ua ntej soldermask | 5µin (0.12µm) -20µin (0.5µm) | Zoo heev solderability;Cov ntaub qhwv yog tiaj thiab sib xws;Al hlau bendability;Tsawg tiv thaiv;Reworkable | Tarnish (kev tuav & cia) corrosion nyob rau hauv siab sulfur ib puag ncig;Txo cov kev xaiv saw hlau los txhawb qhov kev ua tiav no;Lub qhov rais ua haujlwm luv ntawm cov theem sib dhos. | Kev lag luam hloov pauv rau ENIG rau Fine Traces thiab BGA;Zoo tagnrho rau kev kub ceev teeb liab daim ntawv thov;Zoo rau kev hloov pauv membrane, EMI shielding, thiab txhuas hlau txuas;Haum rau nias haum. |
| Immersion Sn | Nyob rau hauv ib tug electroless tshuaj da dej, ib tug dawb nyias txheej ntawm Tin deposits ncaj qha rau tooj liab ntawm Circuit Court boards raws li ib tug barrier kom tsis txhob oxidation. | 25μm (0.7μm) - 60μm (1.5μm) | Qhov zoo tshaj plaws rau xovxwm haum tshuab;Nqi-zoo;Planar;Zoo heev solderability (thaum tshiab) thiab kev ntseeg tau;Flatness | Solderability degradation nrog siab temps & cycles;Exposed tin ntawm lub rooj sib txoos zaum kawg tuaj yeem corrode;Kev daws teeb meem;Tin Wiskering;Tsis haum rau PTH;Muaj Thiourea, lub npe hu ua Carcinogen. | Pom zoo rau ntau qhov ntau lawm;Zoo rau SMD qhov chaw, BGA;Qhov zoo tshaj plaws rau xovxwm haum thiab backplanes;Tsis pom zoo rau PTH, tiv tauj cov keyboards, thiab siv nrog lub qhov ncauj qhov ntswg |
Table2 Kev ntsuam xyuas ntawm cov khoom siv niaj hnub PCB Surface Finishes ntawm kev tsim khoom thiab kev siv
| Kev tsim cov khoom siv feem ntau siv nto tiav | |||||||||
| Cov khoom | ENIG | ENEPIG | Mos Kub | Hard kub | IAg | ISn | HASL | HASL- LF | OSP |
| Nrov nrov | Siab | Tsawg | Tsawg | Tsawg | Nruab nrab | Tsawg | Tsawg | Siab | Nruab nrab |
| Tus nqi txheej txheem | Siab (1.3x) | Siab (2.5x) | Siab tshaj (3.5x) | Siab tshaj (3.5x) | Nruab nrab (1.1x) | Nruab nrab (1.1x) | Tsawg (1.0x) | Tsawg (1.0x) | qis tshaj (0.8x) |
| Tso nyiaj | Kev nqhis dej | Kev nqhis dej | Hluav taws xob | Hluav taws xob | Kev nqhis dej | Kev nqhis dej | Kev nqhis dej | Kev nqhis dej | Kev nqhis dej |
| Txee lub neej | Ntev | Ntev | Ntev | Ntev | Nruab nrab | Nruab nrab | Ntev | Ntev | Luv luv |
| Raws li RoHS | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | No | Yog lawm | Yog lawm |
| Surface Co-planarity rau SMT | Zoo heev | Zoo heev | Zoo heev | Zoo heev | Zoo heev | Zoo heev | pluag | Zoo | Zoo heev |
| Tooj liab | No | No | No | Yog lawm | No | No | No | No | Yog lawm |
| tuav | Ib txwm | Ib txwm | Ib txwm | Ib txwm | Tseem ceeb | Tseem ceeb | Ib txwm | Ib txwm | Tseem ceeb |
| Txheej Txheem Ua Haujlwm | Nruab nrab | Nruab nrab | Siab | Siab | Nruab nrab | Nruab nrab | Nruab nrab | Nruab nrab | Tsawg |
| Rework Peev xwm | No | No | No | No | Yog lawm | Tsis pom zoo | Yog lawm | Yog lawm | Yog lawm |
| Yuav tsum tau Thermal Cycles | ntau | ntau | ntau | ntau | ntau | 2-3 | ntau | ntau | 2 |
| Whisker qhov teeb meem | No | No | No | No | No | Yog lawm | No | No | No |
| Thermal Shock (PCB MFG) | Tsawg | Tsawg | Tsawg | Tsawg | Tsawg heev | Tsawg heev | Siab | Siab | Tsawg heev |
| Tsawg Resistance / Siab ceev | No | No | No | No | Yog lawm | No | No | No | N/A |
| Daim ntawv thov ntawm feem ntau siv nto finishes | |||||||||
| Daim ntawv thov | ENIG | ENEPIG | Mos Kub | Hard kub | IAg | ISn | HASL | LF-HASL | OSP |
| Riam | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm |
| Flex | Txwv tsis pub | Txwv tsis pub | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm |
| Flex-Rigid | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Tsis nyiam |
| Pitch zoo | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Tsis nyiam | Tsis nyiam | Yog lawm |
| BGA & μBGA | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Tsis nyiam | Tsis nyiam | Yog lawm |
| Ntau Solderability | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Txwv tsis pub |
| Flip Chip | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | No | No | Yog lawm |
| Nias Fit | Txwv tsis pub | Txwv tsis pub | Txwv tsis pub | Txwv tsis pub | Yog lawm | Zoo heev | Yog lawm | Yog lawm | Txwv tsis pub |
| Dhau-Qhov | Yog lawm | Yog lawm | Yog lawm | Yog lawm | Yog lawm | No | No | No | No |
| Hlau Bonding | Yog (Al) | Yog (Al, Au) | Yog (Al, Au) | Yog (Al) | Hloov pauv (Al) | No | No | No | Yog (Al) |
| Solder Wettability | Zoo | Zoo | Zoo | Zoo | Zoo heev | Zoo | pluag | pluag | Zoo |
| Solder Joint Integrity | Zoo | Zoo | pluag | pluag | Zoo heev | Zoo | Zoo | Zoo | Zoo |
Lub txee lub neej yog qhov tseem ceeb uas koj yuav tsum xav txog thaum ua koj cov sijhawm tsim khoom.Txee lub neejyog lub qhov rais ua haujlwm uas tso cai rau kev ua tiav kom tiav PCB weldability.Nws yog ib qho tseem ceeb kom paub tseeb tias tag nrho koj cov PCBs tau sib sau ua ke hauv lub txee lub neej.Ntxiv nrog rau cov khoom siv thiab cov txheej txheem uas ua rau saum npoo tiav, txee lub neej ntawm kev ua tiav yog muaj zog cuam tshuamlos ntawm PCBs ntim thiab cia.Tus neeg thov nruj me ntsis ntawm txoj cai cia txoj kev qhia los ntawm IPC-1601 cov txheej txheem yuav khaws cov khoom tiav 'weldability thiab kev ntseeg tau.
Table3 Txee lub neej Kev sib piv ntawm Cov Nto Nto Ua tiav ntawm PCB
|
| Hom SHEL LIFE | Tswvyim Txee Lub Neej | Rework Chance |
| HASL-LF | 12 Lub Hlis | 12 Lub Hlis | YOG |
| OSP | 3 Lub Hlis | 1 Lub Hlis | YOG |
| ENIG | 12 Lub Hlis | 6 hli | TSIS MUAJ* |
| ENEPIG | 6 hli | 6 hli | TSIS MUAJ* |
| Electrolytic Ni/Au | 12 Lub Hlis | 12 Lub Hlis | NO |
| IAg | 6 hli | 3 Lub Hlis | YOG |
| ISn | 6 hli | 3 Lub Hlis | YOG ** |
* Rau ENIG thiab ENEPIG ua tiav lub voj voog rov ua haujlwm los txhim kho qhov chaw ntub dej thiab txee lub neej muaj.
** Chemical Tin rework tsis pom zoo.
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Post lub sij hawm: Nov-16-2022
