Sab saum toj Tin Solder Alloys rau PCB los ua ke

Nyob rau hauv lub realm ntawm electronics manufacturing, solder ua hauj lwm pab raws li ib tug indispensable "bridge" cov ntaub ntawv uas txuas cov luam Circuit Court boards (PCBs) rau cov khoom siv hluav taws xob. Nws tsis tsuas yog tsim kom muaj kev sib txuas hluav taws xob txhim khu kev qha, tab sis kuj txiav txim siab lub zog siv tshuab, kev cia siab ntev - lub sij hawm, thiab kev pab lub neej ntawm cov khoom siv hluav taws xob. Los ntawm cov xov tooj smartphones mus rau aerospace cov cuab yeej, los ntawm cov cuab yeej kho mob mus rau cov khoom siv hluav taws xob hauv tsheb, lub plawv ntawm txhua yam khoom siv hluav taws xob pulses nrog suav tsis txheeb cov pob qij txha.

Nrog rau kev ua raws li European Union cov lus qhia RoHS thiab nce thoob ntiaj teb kev paub txog ib puag ncig, kev lag luam hluav taws xob tau dhau los ua keeb kwm hloov pauv los ntawm kev coj mus rau - dawb solders. Qhov kev hloov pauv no txuas mus deb dhau ntawm kev hloov khoom siv xwb- nws sawv cev rau kev hloov kho tshiab ntawm cov txheej txheem soldering, cov cuab yeej siv, qhov kub thiab txias profiles, thiab kev pov thawj kev ntseeg tau. Kab lus no muab ib qho hauv - tshawb nrhiav qhov tob ntawm qhov tseem ceeb tshaj plaws thauv -raws li solderalloys siv nyob rau hauv PCB los ua ke, ncua los ntawm metallurgical cov hauv paus ntsiab lus mus rau engineering xyaum, los ntawm cov khoom yam ntxwv mus rau txheej txheem optimization, muab electronics manufacturing engineers ib tug kev qhia kev siv.

Metallurgical Fundamentals ntawm Solder Alloys

Soldering Principles thiab Alloy Design

Lub ntsiab lus ntawm kev sib txuas yog siv qhov qis -melting- cov ntsiab lus muab tub lim hlau (solder) uas melts nyob rau hauv tshav kub, ntws mus rau hauv microscopic khoob ntawm cov hlau uas tau koom nrog los ntawm kev ntub dej thiab capillary ua, thiab thaum txias thiab solidification forms intermetallic compound (IMC) kev sib txuas nrog cov cuab yeej tshwj xeeb thiab hluav taws xob conductivity.

Tin (Sn) tau dhau los ua lub hauv paus tseem ceeb ntawm cov khoom siv hluav taws xob vim nws cov khoom siv hluav taws xob tshwj xeeb: nruab nrab melting point (232 degree), wettability zoo heev, zoo hluav taws xob thiab thermal conductivity, thiab muaj peev xwm tsim IMCs ruaj khov nrog PCB pad hlau xws li tooj liab (Cu), nickel (Ni), thiab kub (Au). Txawm li cas los xij, cov tin ntshiab muaj qhov tsis zoo tseem ceeb -nws yog qhov cuam tshuam rau cov kab tsuag tin (ib theem hloov ntawm qhov kub qis ua rau hmoov) thiab tin whisker loj hlob. Yog li ntawd, kev siv tswv yim yeej ib txwm koom nrog kev sib koom ua ke nrog lwm cov hlau.

Lub hom phiaj tseem ceeb ntawm kev tsim alloy nrhiav kev pom zoo sib npaug thoob plaws ntau qhov ntev:

Melting point tswj: Txo qhov melting point los ntawm eutectic los yog ze -eutectic compositions txo thermal shock rau cov khoom thiab substrates

Wettability optimization: Kom ntseeg tau tias molten solder tuaj yeem kis tau thiab nkag mus rau qhov sib txuas

Kho cov cuab yeej cuab tam: Muab lub zog tensile txaus, shear zog, thiab creep kuj

Kev ruaj ntseg: Ua kom muaj kev sib koom tes sib koom ua ke nyob rau hauv ib puag ncig kev ntxhov siab xws li thermal cycling, vibration, thiab av noo

Txheej txheem compatibility: Ua kom haum rau cov txheej txheem sib txawv xws li reflow, yoj, thiab xaiv soldering

Eutectic Alloys thiab Pasty Range

Lub tswv yim tseem ceeb hauv kev nkag siab txog cov alloys yog "eutectic." Eutectic alloys ntawm cov kev sib xyaw tshwj xeeb muaj ib qho chaw melting (ntau dua li qhov sib txawv), hloov ncaj qha los ntawm cov khoom mus rau cov kua thiab vice versa. Cov yam ntxwv no yog ib qho tseem ceeb rau cov txheej txheem soldering-eutectic alloys tsis muaj "pasty" theem thaum lub sij hawm solidification, yog li tsim ntau yam sib xws thiab ntom solder microstructures.

Noj cov tin classic- txhuas alloy ua piv txwv, Sn63 / Pb37 piv yog qhov tseeb ntawm qhov taw tes eutectic nrog lub melting point ntawm raws nraim 183℃. Nyob rau hauv sib piv, Sn60/Pb40 deviates los ntawm eutectic point, nthuav tawm ib tug pasty ntau yam ntawm kwv yees li 7℃(183℃-190℃). Nyob rau hauv no pasty ntau yam, lub solder muaj nyob rau hauv ib tug solid-kua coexistence lub xeev, qhov twg txhua yam kev puas tsuaj tuaj yeem ua rau "txias sib koom ua ke" tsis xws luag.

Ntawm cov hlau lead-dawb solders, eutectic point ntawm SAC alloys nyob ze Sn95.5/Ag3.8/Cu0.7 (SAC387), nrog rau qhov melting point ntawm kwv yees li 217℃. Qhov dav siv SAC305 (Sn96.5/Ag3.0/Cu0.5) me ntsis deviates los ntawm eutectic, muaj ntau yam pasty txog li 3 degree. Txawm li cas los xij, tus cwj pwm no yeej pab txo qis "tombstoneing" tsis xws luag hauv cov khoom siv chip.

Leaded Solder Alloys: Classics thiab Legacy

Lub Tin-Lead Alloy System

Txawm hais tias muaj kev tswj hwm ib puag ncig hnyav zuj zus, cov neeg ua lag luam tseem raug zam rau kev siv hauv tub rog, aerospace, khoom siv kho mob, thiab lwm yam kev siv siab -. Cov teb no xav tau kev sib koom ua ke kev ntseeg siab heev, thiab cov tin - cov hlau lead alloys tau tsim cov ntaub ntawv muaj kev ntseeg siab tshaj plaws los ntawm ntau tshaj li ib nrab xyoo ntawm kev siv tshuab engineering.

Sn63/Pb37 (Eutectic Tin-Tsev)

Qhov no yog qhov feem ntau classic solder formulation nyob rau hauv electronics kev lag luam keeb kwm. Lub eutectic melting point ntawm 183℃muab ib tug dav txheej txheem qhov rais, nrog ib txwm reflow ncov kub tsuas yog 205-215℃-degree hauv qab 240-245℃yuav tsum tau rau cov hlau lead-free solders. Low-temperature soldering txhais tau tias:

Txo cov thermal kev nyuab siab ntawm cov khoom, tshwj xeeb tshaj yog muaj txiaj ntsig rau cov cua sov- qhov tseem ceeb xws li electrolytic capacitors thiab optoelectronic li

Txo PCB warpage thiab deformation

Cov khoom siv txuas ntxiv lifespan thiab qis zog siv

Los ntawm qhov kev xav ntawm microstructural, Sn63 / Pb37 tsim ib qho qauv lamellar eutectic qauv nrog alternating tin thiab lead theem, muab kev qaug zog zoo heev. Lub xub ntiag ntawm cov hmoov txhuas kuj ua rau muaj txiaj ntsig zoo rau kev loj hlob ntawm tin whisker-ib qho ntawm cov kev ntseeg siab loj tshaj plaws uas ntsib cov hlau lead- dawb solders.

Sn60/Pb40

Tus nqi qis dua Sn63 / Pb37, tab sis deviates los ntawm eutectic point, ua rau muaj ntau yam pasty. Nyob rau hauv phau ntawv soldering scenarios, tus yam ntxwv no yeej muab ntev "lub sij hawm ua hauj lwm," cia solderers kho cov pob qij txha.

Sn62 / Pb36 / Ag2 (Ternary Alloy)

Ntxiv 2% nyiaj coj cov kev txhim kho tseem ceeb: nyiaj txo qis cov kua dej kub ntawm cov solder thiab txhim kho wettability. Qhov tseem ceeb tshaj, nyiaj cov tshuaj tiv thaiv nrog cov tooj liab pad txheej slows tus nqi dissolution ntawm tooj liab mus rau hauv lub solder matrix, extending solder lauj kaub lub neej nyob rau hauv tas li ntawd mus ua hauj lwm zoo li yoj soldering. Silver ntxiv kuj tseem txhim kho hluav taws xob conductivity thiab corrosion kuj ntawm cov pob qij txha.

High -Tub kub Leaded Solders

Qee daim ntawv thov tshwj xeeb xav tau cov pob qij txha kom ruaj khov nyob rau hauv siab - qhov kub thiab txias. Txij li cov hlau lead ntshiab muaj qhov melting point siab li 327 degree, siab - txhuas alloys yog qhov kev xaiv rau siab - kub solders.

Sn10/Pb88/Ag2

Nrog lub melting point ntawm kwv yees li 299 degree, qhov no alloy yog haum rau huab cua siab heev -kub ib puag ncig xws li aircraft cav tswj systems thiab downhole roj thiab roj khoom. Cov alloys no feem ntau yog siv los ua "thawj- kauj ruam soldering" cov ntaub ntawv, nrog cov txheej txheem tom qab siv qis- melting-point solders rau "step soldering" kom ntseeg tau tias siab -kub pob qij txha tsis rov- melted.

Lead-Dawb Solder Alloys: Workhorses of the Environmental Era

SAC Alloy Tsev Neeg

SAC (Sn-Ag-Cu, tin-silver-copper) alloys yog lub ntsiab tseem ceeb hauv kev lag luam hluav taws xob niaj hnub no. Txij li thaum RoHS cov lus qhia tau siv rau xyoo 2006, SAC alloys tau txais txiaj ntsig kev lag luam tsis tu ncua hauv cov khoom siv hluav taws xob, kev tswj hwm kev lag luam, cov khoom siv sib txuas lus, thiab lwm yam. Kev txheeb cais qhia tias SAC alloys suav txog ntau dua 65% ntawm cov hlau lead-kev ua lag luam dawb.

SAC305 (Sn96.5/Ag3.0/Cu0.5)

Qhov no yog cov "nyiam" lead-dawb alloy pom zoo los ntawm IPC's Solder Products Value Council thiab tau txais kev pom zoo thoob ntiaj teb. Nws txoj kev vam meej yog los ntawm kev sib npaug ntawm ntau yam:

Melting Point thiab Processability: Lub 217-220℃melting point, thaum 34℃siab tshaj tin-lead eutectic, tseem nyob rau hauv lub kub kam rau ntawm feem ntau hluav taws xob Cheebtsam. Qhov ntsuas kub ntawm qhov ntsuas kub ntawm qhov ntsuas kub yog 235-245 degree, nrog lub sij hawm siab tshaj li kua (TAL) tswj rau 60-90 vib nas this.

Mechanical Properties: SAC305 lub zog tensile yog kwv yees li 40-50 MPa, siab dua Sn63/Pb37's 25-35 MPa. Qhov no feem ntau yog ntaus nqi rau kev sib zog ua kom muaj zog ntawm Ag3Sn intermetallic compounds tsim los ntawm nyiaj. Txawm li cas los xij, lub zog siab dua kuj txhais tau tias qis dua ductility, uas ua rau muaj kev ua haujlwm tsis zoo piv rau tin-lead solder hauv kev ntsuas kev poob qis.

Kev ntub dej: Muab piv rau tin-cov hmoov txhuas, SAC305 muaj lub kaum sab xis loj dua (kwv yees li 30℃vs 15 degree) thiab qeeb wetting ceev. Qhov no yuav tsum tau siv ntau cov fluxes los yog optimizing soldering kub profiles.

Thermal Fatigue Resistance: SAC305 ua tau zoo heev hauv kev ntsuas kev ntsuas cua sov (-40℃rau +125 degree), nrog rau kev sib koom ua ke lub neej piv rau lossis ntau tshaj tin-lead solder. Qhov no yog vim Ag3Sn theem pins grain ciam zawv zawg, ncua kev qaug zog tawg tawm.

Tus nqi Factors: Nyiaj tus nqi hloov pauv cuam tshuam rau SAC305 tus nqi. Thaum cov nqi nyiaj tau tshaj $ 40 / oz hauv xyoo 2011, kev lag luam nquag nrhiav qis - nyiaj hloov pauv.

SAC387 (Sn95.5/Ag3.8/Cu0.7)

Kaw rau qhov tseeb ternary eutectic taw tes, nthuav tawm sharper melting cwj pwm. Cov ntsiab lus nyiaj ntau dua muab cov thermal qaug zog me ntsis zoo dua li SAC305, ua rau nws tsim nyog rau cov ntawv thov uas muaj qhov kub thiab txias hloov pauv xws li lub tshuab hluav taws xob hauv tsheb thiab cov khoom siv tswj kev lag luam. Cov thawj coj thaum ntxov- cov pioneers dawb zoo li Motorola pib tsim cov xov tooj ntawm tes nrog SAC387 thaum ntxov li 2001.

SAC105 (Sn98.5/Ag1.0/Cu0.5)

Ib qho qis-silver alloy tsim los teb rau cov nqi nyiaj nce thiab txo cov kev xav tau ntawm cov khoom siv nqa tau yooj yim. Kev tshawb fawb qhia tau hais tias txo cov ntsiab lus nyiaj txo qhov ntim feem ntawm nkig Ag3Sn theem, txhim kho cov yas deformation muaj peev xwm ntawm cov pob qij txha thiab yog li txhim kho kev poob qis. iNEMI (International Electronics Manufacturing Initiative) kev sim ua kom pom tias SAC105 ua tau zoo dua SAC305 hauv kev xeem poob. Txawm li cas los xij, cov ntsiab lus ntawm cov nyiaj qis dua ua rau muaj kev ntseeg siab ntawm kev sib tw, yog li SAC105 feem ntau yog siv rau hauv cov khoom siv hluav taws xob xws li smartphones thiab ntsiav tshuaj.

Doped Hloov SAC Alloys

Txhawm rau txhim kho kev ua tau zoo ntxiv, cov kws tshawb fawb tau tsim ntau yam SAC alloys nrog cov kab txuas ntxiv:

SAC+Mn/Ce: Ntxiv cov lej (<0.1%) of manganese or cerium significantly improves both drop impact and thermal cycling performance

SAC+Bi: Bismuth ntxiv txhim kho wettability, txo cov ntsiab lus melting, thiab txo qhov sib koom ua ke voiding

SAC+Ni: Nickel tiv thaiv lub hauv paus metallization txheej los ntawm kev tawg ntau dhau

SAC + SIB: Antimony txhim kho cov neeg kho tshuab lub zog thaum tiv thaiv tin whiskers

Tin-Topper Alloys (Sn-Cu)

Sn99.3/Cu0.7

Cov hlau lead yooj yim tshaj plaws - dawb binary alloy nrog lub melting point ntawm kwv yees li 227 degree, txog 7℃siab dua SAC305. Qhov zoo tshaj plaws ntawm tin - tooj liab alloys yog tus nqi - tshem tawm cov nyiaj kim heev ua rau lawv xaiv kev lag luam rau yoj soldering thiab phau ntawv soldering.

Txawm li cas los xij, cov tin ntshiab - tooj liab alloys muaj cov dej tsis zoo thiab cov khoom siv tshuab piv rau SAC series. Txhawm rau daws cov teeb meem no, kev lag luam tau tsim ntau yam kev hloov kho:

SN100C (Sn-0.7Cu-0.05Ni + Ge)

Nrog rau qhov sib ntxiv ntawm cov kab nickel thiab germanium, SN100C's wettability mus txog SAC305, thiab tooj liab dissolution qeeb qeeb, ncua yoj lub lauj kaub tu lub sijhawm. Germanium txo oxidation thiab dross tsim.

K100 (Sn-Cu-Ni Series)

Ib qho alloy optimized rau yoj soldering, qhov twg nickel ntxiv cov ntaub ntawv (Cu, Ni) 6Sn5 intermetallic compound txheej txheej uas ruaj khov dua li ntshiab Cu6Sn5, ncua kev loj hlob ntawm IMC interfacial ntau dhau.

Tin-Bismuth qis-Tub kub Alloys (Sn-Bi)

Tsawg-kub soldering thev naus laus zis tau ntxim nyiam nyob rau xyoo tas los no, tau tsav los ntawm:

Cov kev xav tau los ua ke rau qhov kub thiab txias - cov khoom tseem ceeb (xws li MEMS thiab qee cov sensors)

Txo PCB thiab BGA pob warpage

Kev txuag hluav taws xob, txo qis emission, thiab txo cov pa roj carbon hneev taw

"thib ob-step" qis-kub soldering hauv cov txheej txheem soldering

Sn42/Bi58 (Eutectic Tin-Bismuth)

Nrog lub melting point ntawm tsuas yog 138 degree, qhov no yog qhov qis tshaj melting point siv lead ua - dawb solder. Qhov ntsuas kub ntawm qhov ntsuas kub tuaj yeem tswj tau rau 170-180 degree, kwv yees li 70℃qis dua SAC305. Qhov no txhais tau tias:

Txo qhov kev pheej hmoo ntawm kev puas tsuaj rau cov cua sov- cov khoom rhiab heev

Kev txo qis thermal warpage hauv PCBs thiab BGAs

Tsawg reflow qhov cub siv hluav taws xob thiab siv lub neej ntev

Txawm li cas los xij, bismuth's inherent brittleness yog Achilles lub pob taws ntawm Sn-Bi alloys. Ntshiab Sn42/Bi58 muaj qhov elongation ntawm 1-2%, deb tshaj SAC305's 20-40%. Qhov no ua rau cov pob qij txha tawg yooj yim nyob rau hauv kev cuam tshuam los yog khoov kev ntxhov siab. Tsis tas li ntawd, qhov kub-kub aging ua rau bismuth cais ntawm cov interfaces, ntxiv degrading mechanical zog.

Sn42/Bi57/Ag1

Ntxiv 1% nyiaj pab txhim kho wettability thiab qaug zog tiv thaiv thaum tswj qhov qis melting point zoo. Lub Ag3Sn theem tsim los ntawm nyiaj refines lub microstructure rau qee qhov, txhim kho ductility.

Tsis yog -Eutectic Sn-Bi Alloys

Kev tshawb fawb qhia tau hais tias alloys deviating los ntawm eutectic muaj pes tsawg leeg (xws li Sn -Bi nrog 40% Bi los yog qis dua) muaj zoo mechanical zog. Cov ntsiab lus bismuth qis dua txo qhov ntim feem ntawm cov theem nkig thaum tuav cov ntsiab lus qis melting.

Siv zog Sn-Bi Composite Solders

Txhawm rau kov yeej cov teeb meem brittleness, kev lag luam tau tshawb nrhiav ntau yam kev txhawb nqa:

Epoxy-cov khoom siv zog ntxiv: Ntxiv cov khoom siv epoxy rau cov tshuaj txhuam hniav ua cov txheej tiv thaiv encapsulating solder pob qij txha tom qab reflow

nanoparticle reinforcement: Ntxiv nanoparticles zoo li NiO thiab TiO2 los ua kom zoo dua cov qauv nplej

Hybrid soldering technology: Siv qis -kub Sn-Bi solder paste ua ke nrog SAC305 solder balls kom tiav cov pob qij txha ntawm qhov kub qis

Lwm Yam Khoom Tshwj Xeeb

Sn-Ag (Binary Tin-Silver)

Sn96.5/Ag3.5 yog ib qho tseem ceeb ntawm cov hlau lead thaum ntxov- kev tshawb fawb dawb solder, nrog lub melting point ntawm 221 degree, ze rau SAC series. Ntshiab tin-silver alloys muaj dej zoo dua li SAC tab sis tus nqi siab dua, thiab tsis muaj qhov cuam tshuam txog kev loj hlob ntawm IMC interfacial uas tooj liab muab.

Sn{0}}Zn (Tin-Zinc)

Sn91/Zn9 eutectic alloy muaj qhov melting point tsuas yog 199 degree, nruab nrab ntawm tin- txhuas thiab SAC, thiab ib zaug suav hais tias yog ib qho kev cog lus lead- tus neeg sib tw dawb. Txawm li cas los xij, zinc lub siab reactivity ua rau muaj teeb meem oxidation hnyav, yuav tsum muaj kev tiv thaiv huab cua thaum lub sij hawm soldering. Zinc's corrosiveness rau tooj liab pads kuj yog ib qho kev txwv tsis pub siv.

Sn-In (Tin-Indium)

Indium tuaj yeem txo cov ntsiab lus melting ntau heev (Sn-52In eutectic point tsuas yog 118 degree) thiab muaj kev sib raug zoo nrog kub, ua rau nws haum rau kub hlau sib txuas thiab kub kub tuag txuas. Txawm li cas los xij, indium qhov tsis txaus, tus nqi siab, thiab kev cuam tshuam rau corrosion txwv nws daim ntawv thov ntau yam.

Flux: Tus Saib Xyuas Tsis Pom Zoo ntawm Kev Ua Haujlwm Zoo

Flux Mechanism of Action

Txawm hais tias qhov zoo tshaj plaws ntawm solder alloy nws tus kheej yuav zoo li cas, cov txheej txheem soldering tsis tuaj yeem ua tiav yam tsis muaj qhov tsim nyog flux. Cov haujlwm tseem ceeb ntawm flux muaj xws li:

Kev tshem tawm Oxide: Hlau nto tsim oxide zaj duab xis nyob rau hauv cov huab cua uas tiv thaiv solder wetting. Cov khoom nquag hauv flux (xws li cov organic acids thiab halides) hnov ​​​​mob nrog oxides thaum rhuab, dissolving los yog hloov lawv mus rau volatile tebchaw.

Re-Kev tiv thaiv oxidation: Nyob rau ntawm qhov kub thiab txias, flux npog cov npoo hlau tsim ib txheej tiv thaiv uas cais cov pa oxygen.

Nto Nrho Kev Txom Nyem: Surfactants hauv flux txo qhov nro ntawm cov molten solder, txhawb kev sib kis ntawm cov ntaub qhwv.

Thaum tshav kub kub hloov nruab nrab: Kua flux pab hloov cov cua sov uniformly mus rau lub soldering interface.

Flux Classification System

Raws li IPC J-STD-004 tus qauv, flux yog cais los ntawm cov khoom siv hauv paus thiab qib ua haujlwm:

Rosin-Based Flux

Rosin yog ib yam khoom ntuj muab rho tawm los ntawm ntoo thuv resin, feem ntau muaj li ntawm abietic acid. Rosin-raws li flux muaj keeb kwm ntev thiab kev ua haujlwm ruaj khov, sawv cev rau kev xaiv ib txwm siv rau kev siv hluav taws xob.

R (Rosin): Ntshiab rosin nrog kev ua haujlwm qis tshaj plaws, tsuas yog tsim rau cov chaw ntxuav nrog oxidation tsawg

RMA (Rosin Mildly Activated): Muaj me me ntawm cov activators nrog kev ua haujlwm nruab nrab thiab cov seem me me

RA (Rosin Activated): Cov ntsiab lus ntawm cov activator siab dua, haum rau ntau qhov chaw oxidized hnyav, residues yuav tsum tau ntxuav

Rosin flux residues yog khoom, tsis yog -conductive, thiab chemically inert nyob rau hauv chav tsev kub. Kev lig kev cai, R thiab RMA residues raug txiav txim siab tso cai tawm ntawm lub rooj tsav xwm hauv Circuit Court, tab sis niaj hnub high - circuits ceev xav tau kev huv huv, thiab ntau daim ntawv thov tseem pom zoo kom ntxuav.

Dej-Soluble Flux

Siv cov organic acids (xws li citric acid thiab adipic acid) ua cov khoom xyaw nquag, feem ntau yog tsim nrog dej -cov cab kuj zoo li ethylene glycol. Dej- cov kua dej soluble muaj qhov ua haujlwm siab tshaj plaws, muaj peev xwm tshem tawm cov tawv tawv oxide txheej, haum rau qhov nyuaj - mus rau - solder nto los yog hnyav oxidized qhov qub.

Txawm li cas los xij, kev ua haujlwm siab kuj txhais tau tias muaj kev pheej hmoo siab corrosion. Cov dej- cov dej soluble flux residues muaj cov ions nquag uas, yog tias tsis tau muab tshem tawm kom zoo, tuaj yeem ua rau electrochemical migration, to, los yog luv luv Circuit Court nyob rau hauv high - av noo ib puag ncig. Yog li ntawd, cov txheej txheem tu dej nruj yuav tsum ua raws li kev siv dej -soluble flux.

Tsis yog -Clean Flux

Tsim los kom yooj yim cov txheej txheem ntws thiab txo cov nqi. Nws lub tswv yim tsim yog: cov khoom siv ua kom tiav lawv txoj haujlwm deoxidation ntawm qhov kub thiab txias, tom qab ntawd cov khoom seem tseem nyob hauv qhov tsis muaj - conductive, tsis yog - corrosive lub xeev uas muaj kev nyab xeeb nyob rau hauv Circuit Court boards.

Tsis yog- cov dej huv huv feem ntau yog siv cov khoom siv cov ntsiab lus qis (1-5%), nrog rau feem ntau cov tshuaj nquag volatilizing lossis decomposing thaum lub sij hawm reflow. Cov nyiaj seem tsawg tsawg thiab muaj tshuaj lom neeg ruaj khov. Qhov no ua rau nws qhov kev xaiv zoo tshaj plaws rau siab -SMT cov kab ntau lawm-tawm cov txheej txheem ntxuav txhais tau tias lub sij hawm luv luv, cov cuab yeej siv qis dua, thiab txo kev siv tshuaj lom neeg.

Txawm li cas los xij, "tsis yog- huv" tsis txhais hais tias "tsis muaj residue." Hauv siab - daim ntawv thov kev ntseeg siab (aerospace, kho mob implants) lossis siab - zaus circuits, txawm tias qhov seem seem yuav cuam tshuam rau kev ua haujlwm. Yog li ntawd, cov ntawv thov no feem ntau tseem xaiv cov txheej txheem ntxuav.

Flux Selection Strategy

Kev xaiv Flux yuav tsum muaj kev xav zoo ntawm cov hauv qab no:

Surface Condition of Soldering Objects: Tshiab tsim tin- cov khoom siv plated muaj tsawg kawg nkaus oxidation thiab tuaj yeem siv qis- ua haujlwm flux; Cheebtsam nrog lub sij hawm cia ntev los yog kev kho deg tsis zoo yuav tsum muaj siab - ua haujlwm flux.

Solder Alloy Hom: Lead-cov solders dawb feem ntau muaj cov dej tsis zoo piv rau cov tin- cov hlau lead, feem ntau yuav tsum tau muaj dej ntau dua.

Muaj peev xwm ntxuav tau: Yog tias cov kab ntau lawm muaj cov cuab yeej siv ua tiav (ultrasonic, cov tshuab tshuaj tsuag), dej - cov kua dej soluble tuaj yeem raug xaiv rau cov txiaj ntsig zoo tshaj plaws; txwv tsis pub, tsis muaj - huv lossis rosin-raws li yuav tsum tau xaiv.

Yam Khoom Muaj Kev Ntseeg Siab: IPC Chav Kawm 3 (siab-kev ntseeg siab) cov khoom lag luam feem ntau xav tau kev ntxuav cov seem lossis siv cov ntawv pov thawj nruj me ntsis tsis muaj- ntxuav flux.

Environmental Regulations: Qee thaj chaw muaj kev txwv nruj ntawm VOC (volatile organic compound) emissions, xav tau dej-raws li lossis qis-VOC formulations.

Tin Whiskers: Kev ntseeg siab npau suav phem ntawm cov Lead -Dawb Era

Tin Whisker Phenomenon thiab Hazards

Tin whiskers yog filamentary ib leeg - cov qauv siv lead ua uas tshwm sim los ntawm cov tin ntshiab lossis siab - tin alloy nto, feem ntau yog 1-5 micrometers inch thiab ntau pua micrometers mus rau ob peb millimeters ntev. Cov hlau yuav luag tsis pom "cov plaub hau" ua rau muaj kev hem thawj loj rau kev ntseeg tau ntawm cov cuab yeej hluav taws xob.

Mechanisms uas tin whiskers ua rau tsis ua hauj lwm muaj xws li:

Luv Circuits: Tin whiskers bridging nyob ib sab conductors ua rau hluav taws xob luv. Nyob rau hauv siab - pob qhov ntom ntom (0.5mm suab thiab hauv qab), whiskers tsuas yog kaum micrometers ntev tuaj yeem ua rau muaj kev puas tsuaj.

Arc tso tawm: Nyob rau hauv qhov chaw siab -voltage, tin whiskers tuaj yeem ua rau arcing, ua rau tam sim no siab - kub melting, tshwj xeeb tshaj yog txaus ntshai nyob rau hauv lub tshuab nqus tsev los yog qis- qhov chaw siab (xws li satellites thiab siab - cov khoom siv qhov siab).

Debris Contamination: Tin whiskers tuaj yeem tawg, tsim cov khoom khib nyiab hauv cov khoom siv uas ua rau tsis sib xws.

Keeb kwm, tin whiskers tau ua rau ntau qhov xwm txheej nto moo:

Galaxy IV Satellite (1998): Tag nrho cov satellite ua tsis tiav vim tin whisker luv circuits hauv lub computer tswj, ua rau ntau pua lab nyiaj poob rau hauv

Millstone Nuclear Power Plant (2005): Tin whiskers ua rau lub zog ntsuas qhov ntsuas qhov ntsuas tsis raug, ua rau muaj kev kaw thaum muaj xwm txheej ceev

Toyota "Phantom Acceleration" xwm txheej (hais txog hauv kev tshawb nrhiav): Qee cov kws tshawb fawb pom cov tin whiskers nyob rau hauv qhov chaw throttle sensors, txawm hais tias qhov kev tshawb nrhiav qhov kawg txiav txim siab qhov ua rau

Tin Whisker Formation Mechanism

Txawm hais tias qhov tshwm sim tin whisker tau tshawb pom thaum ntxov li xyoo 1940, nws cov txheej txheem tsim muaj tseeb tseem tsis to taub. Tam sim no lees paub qhov tseem ceeb tsav tsheb yogcompressive kev nyuaj siab:

Intermetallic Compound Growth Stress: Thaum tin plating hu rau tooj liab substrate, tooj liab atoms diffuse rau hauv tin txheej, tsim Cu6Sn5 intermetallic compounds ntawm lub interface. IMC ntim expansion tsim compressive kev nyuaj siab nyob rau hauv lub tin txheej.

Thermal Expansion Coefficient Mismatch: Qhov sib txawv ntawm coefficient ntawm thermal expansion (CTE) ntawm tin thiab substrates zoo li tooj liab thiab npib tsib xee ua rau interfacial kev nyuaj siab txuam nrog qhov kub thiab txias.

Mechanical Stress: Cov khoom siv lead ua dabtsi yog khoov, nias- haum, kev co, thiab lwm yam kev ua haujlwm ua haujlwm tsim kom muaj kev ntxhov siab hauv zos.

Corrosion-Kev ntxhov siab vim: Ionic contamination (xws li chloride thiab sulfide ions) pib corrosion hauv zos, nrog oxide khoom ntim hloov ua kev ntxhov siab.

Lub ntsiab lus ntawm tin whisker kev loj hlob yog cov txheej txheem uas cov tin muaju tso tawm sab hauv kev ntxhov siab los ntawm grain ciam diffusion thiab dislocation motion. Thaum muaj kev ntxhov siab ntau tshaj qhov tseem ceeb, tin atoms tsiv teb tsaws raws cov lus qhia tshwj xeeb crystallographic thiab "extrude" los tsim cov pob zeb ntawm qhov chaw.

Qhov tseem ceeb, yog vim li cas cov hlau lead ntxiv suppresses tin whisker kev loj hlob yog feem ntau: txhuas atoms segregate rau tin grain ciam teb, impeding grain ciam diffusion; tib lub sij hawm, lub xub ntiag ntawm lead theem hloov tin's grain qauv, txhawb nqa kev ntxhov siab ib yam.

Tin Whisker Mitigation Strategies

Txij li thaum tin whisker qhov kev pheej hmoo tsis tuaj yeem raug tshem tawm tag nrho, kev lag luam siv ntau -theem txo cov tswv yim:

Khoom Qib

Nickel Barrier Txheej: Ntxiv cov nickel plating txheej (1-2 micrometers) ntawm tooj liab substrate thiab tin plating blocks tooj liab diffusion rau hauv tin, tshem tawm IMC kev loj hlob kev nyuaj siab.

Tin-Kev kho cov hmoov txhuas / Kub Dip: Immersing ntshiab tin plated Cheebtsam nyob rau hauv tin- lead solder qhia ua rau suppress whiskers

Matte Tin Hloov Bright Tin: Loj-grain matte tin plating muaj kev ntxhov siab tsawg dua li me me -grain ci tin

Ntxiv ntawm Bismuth thiab lwm yam Alloying Elements: Trace bismuth tuaj yeem hloov cov tin cov qauv, muab kev tiv thaiv zoo ib yam li txhuas

Txheej txheem theem

Kev kho mob Annealing: Kev kho ntawm 150℃rau 1 teev los yog siab dua kub txhawb kev ntxhov siab

Kev kho mob Fusing: Heating pure tin plating above melting (>232 degree) ces txias tshem tawm plating kev nyuaj siab

Solder Coverage: Los ntawm soldering, cov hlau lead ntshiab yog tag nrho los ntawm tin - txhuas los yog SAC solder

Tsim Qib

Conformal Txheej: Siv 2-3 mil tuab polyurethane, acrylic, los yog silicone txheej tom qab PCB los ua ke lub cev blocks tin whisker loj hlob los yog tiv thaiv kev nkag mus ua luv luv.

Nce tus neeg xyuas pib sib nrug: Tso cai rau kev nyab xeeb margins rau tin whisker loj hlob nyob rau hauv Circuit Court tsim

Xaiv Cheebtsam yam tsis muaj ntshiab Tin Plating: Qhia txog lwm txoj kev kho deg zoo li NiPdAu, tin- txhuas, lossis SAC pob

Kev Tshawb Nrhiav thiab Saib Xyuas

Ua kom ceev cov tin whisker kev loj hlob kev ntsuam xyuas (kub- vaum caij tsheb kauj vab, siab- kub siab- av noo cia) raws li JEDEC JESD201 tus qauv

Kev tshuaj xyuas tsis tu ncua ntawm thaj chaw tseem ceeb siv SEM (scanning electron microscope)

Tsim cov khoom lag luam tin whisker kev soj ntsuam kev pheej hmoo

Soldering txheej txheem thiab kub Profile Optimization

Reflow Soldering

Reflow soldering yog cov txheej txheem tseem ceeb ntawm nto mount thev naus laus zis (SMT), nrog rau qhov yooj yim ntws:

Solder paste yog luam tawm rau hauv PCB pads los ntawm stencil

Xaiv-thiab- muab cov tshuab tso cov khoom sib xyaw rau hauv cov tshuaj txhuam hniav

Lub PCB dhau los ntawm qhov cub reflow qhov twg cov tshuaj txhuam tau yaj los ua cov pob qij txha

Plaub theem ntawm Temperature Profile

Preheat Zone: Cua sov PCB los ntawm chav tsev kub mus rau 150-200℃ntawm ramp tus nqi ntawm 1-3℃/ thib ob, volatilizing cov kuab tshuaj nyob rau hauv lub solder paste thaum tsis txhob thermal shock

Soak Zone: Khaws qhov kub thiab txias hauv 150-200℃ntau rau 60-120 vib nas this, ua kom lub rooj tsavxwm zoo sib xws thiab ua kom cov dej ntws tawm kom pib tshem tawm oxide

Reflow Zone: Ua kom kub ceev kom kub siab tshaj (kwv yees li 235-245℃rau SAC305, 205-215℃rau tin-lead) qhov twg solder melts los tsim cov pob qij txha. Lub Sijhawm Saum Ntuj Liquidus (TAL) yog tswj rau 60-90 vib nas this

Txias Zone: Txias rau chav sov ntawm tus nqi ntawm 2-4℃/ thib ob. Tsim nyog cov nqi cua txias pab tsim cov qauv zoo, zoo ib yam li nplej

Kev txiav txim siab tshwj xeeb rau Lead -Free Soldering

Lub melting point siab dua ntawm cov hlau lead- dawb solder nthuav qhia cov kev cov nyom rau cov txheej txheem reflow:

Peak kub nce los ntawm kwv yees li 30 degree, muaj peev xwm tshaj qhov ntsuas kub ntawm qee qhov cua sov- cov khoom rhiab heev (electrolytic capacitors, yas connectors)

Kev kub siab dua ua rau PCB thiab BGA warpage, ua rau kev sib koom ua ke kev ntxhov siab

Kev tswj qhov kub thiab txias ntau yog yuav tsum tau ua kom txhua qhov sib koom ua ke mus txog qhov kub thiab txias

Nitrogen tiv thaiv huab cua tuaj yeem txhim kho wettability thiab txo oxidation

Wave Soldering

Wave soldering feem ntau yog siv rau batch soldering ntawm los ntawm - qhov khoom thiab hauv qab - sab soldering ntawm sib xyaw ua ke boards. PCB hauv qab tiv tauj txuas ntxiv txuas ntxiv molten solder vuag, nrog cov khoom siv nkag los ntawm - qhov ntawm kev ua haujlwm capillary thiab cov khoom ntub dej ua rau.

Wave Solder Management

Solder lauj kaub muaj pes tsawg leeg tswj hauv yoj soldering yog qhov tseem ceeb. Raws li soldering zuj zus, cov kab mob hauv qab no maj mam sib sau:

Tooj Liab: PCB copper layers and component leads release copper into the solder; excessive copper content (>0.3%) txo fluidity

Oxidation Dross: Solder nto oxidation cov ntaub ntawv dross, nce cov khoom poob

Lwm yam impurities: Nickel, kub, thiab lwm yam khoom los ntawm PCB nto kev kho mob maj mam mloog zoo

Kev txheeb xyuas qhov sib xyaw ntawm cov khoom siv thiab cov khoom siv tshiab tshiab yog qhov tsim nyog rau kev saib xyuas. Tin- tooj liab alloys (xws li SN100C), vim lawv qis tooj liab saturation solubility, muaj lub neej ntev nyob rau hauv yoj soldering tshaj SAC305.

Selective Soldering

Selective soldering yog ib txheej txheem ntawm yoj soldering thiab phau ntawv soldering, siv programmable soldering hau rau precisely solder tej thaj chaw. Cov txheej txheem no haum rau:

Los ntawm -lub qhov soldering ze ntawm tshav kub- cov khoom rhiab heev

Areas on high-density boards where wave soldering cannot be performed

Cov sib tov sib xyaw yuav tsum tau sib txawv solder alloys

Selective soldering systems feem ntau suav nrog peb modules rau flux spraying, preheating, thiab soldering, nrog rau cov tsis customizable rau txhua tus yam ntxwv ntawm solder.

Kev soj ntsuam kev ntseeg siab thiab kev lag luam Standards

Solder Joint Reliability Evaluation Methods

Thermal Cycling Testing

Simulates qhov kub thiab txias hloov tau los ntawm cov khoom siv hluav taws xob thaum siv. Cov xwm txheej yog -40℃rau +125℃cycles, nrog rau 30-60 feeb ib lub voj voog. Cov pob qij txha maj mam txhim kho kev qaug zog ntawm cov kab nrib pleb nyob rau hauv strain tshwm sim los ntawm thermal expansion coefficient mismatch. Kev ntsuam xyuas feem ntau txuas ntxiv mus rau ntau pua mus rau ntau txhiab lub voj voog kom txog thaum sib koom ua ke ua haujlwm nce ntxiv lossis ua tiav qhib tshwm sim.

Kub-Kev ntsuas av noo

Ntsuam xyuas corrosion kuj thiab electrochemical migration nyiam ntawm solder pob qij txha nyob rau hauv siab - kub, siab - av noo ib puag ncig. Cov xwm txheej yog 85℃/ 85% RH rau ntau tshaj 1000 teev. Qhov kev sim no tshwj xeeb tshaj yog nthuav tawm qhov kev pheej hmoo ntawm kev ntseeg siab los ntawm cov dej ntws tawm.

Poob Impact Test

Simulates portable ntaus ntawv poob scenarios. Cov PCBs sib dhos yog tsau rau hauv cov qauv kev sib tw thiab poob los ntawm qhov siab tau teev tseg (xws li 1.5 meters) mus rau qhov chaw nruj, rov ua dua kaum rau ntau pua zaus. Tus naj npawb ntawm cov tee rau kev sib koom ua ke tsis ua haujlwm thiab cov hom tsis ua haujlwm raug kaw. SAC alloys, tshwj xeeb tshaj yog siab - silver formulations, yuav ua tau tsis zoo nyob rau hauv qhov kev xeem no.

Khoov Kev Xeem

Ntsuam xyuas kev sib koom ua ke ntawm kev puas tsuaj nyob rau hauv PCB dabtsi yog khoov deformation. Plaub-point lossis peb- taw tes dabtsi yog khoov fixtures siv tswj strain thaum saib xyuas cov khoom siv hluav taws xob txuas ntxiv.

Shear Strength Test

Ntsuas cov khoom siv dag zog ntawm cov pob los yog cov pob qij txha siv micro-shear testers. Qhov no yog ib qho kev ntsuas yooj yim rau kev ntsuas cov khoom zoo thiab sib piv cov hlau sib txawv / txheej txheem.

IPC Standards System

Cov qauv tsim los ntawm IPC (Association Connecting Electronics Industries) yog cov qauv kev tso cai rau kev lag luam hluav taws xob thoob ntiaj teb:

J-STD-001 "Yuav tsum muaj rau Soldered Electrical thiab Electronic Assemblies"

Qhov no yog tus qauv tseem ceeb rau cov txheej txheem soldering thiab kev tswj kom zoo, npog:

Cov khoom yuav tsum muaj: Specifications rau solder, flux, thiab PCB nto tiav

Cov txheej txheem yuav tsum tau: Tswj preheating, soldering kub, thiab lub sij hawm tsis

Kev lees txais cov qauv: Cov qauv txiav txim rau kev sib koom ua ke zoo li qub, lub kaum sab xis ntub dej, thiab sau qhov siab

Kev tswj ib puag ncig: Kub thiab av noo, kev tiv thaiv ESD, thiab kev huv huv

J-STD-001 muab cov khoom faib ua peb theem:

Qib 1: Cov khoom siv hluav taws xob dav dav (consumer electronics)

Chav Kawm 2: Kev pabcuam khoom siv hluav taws xob tshwj xeeb (kev lag luam, kev sib txuas lus)

Chav Kawm 3: High-cov khoom siv hluav taws xob ua tau zoo (tub rog, aerospace, kho mob)

Cov chav kawm siab dua muaj cov kev xav tau nruj dua rau kev sib koom ua ke zoo thiab kev tswj cov txheej txheem.

J-STD-002 "Solderability Tests for Component Leads, Terminations, Lugs, Terminals thiab Wires"

Qhia meej cov txheej txheem rau kev ntsuam xyuas solderability ntawm cov khoom siv lead ua thiab kev txiav tawm, suav nrog:

Dip Test: Ntsuas qhov℃ntawm solder wetting ntawm leads

Wetting Balance Test: Quantitatively ntsuas wetting force variation curves over time

Reflow Test: Simulates BGA solder pob wetting cwj pwm nyob rau hauv SMT reflow tej yam kev mob

J-STD-003 "Solderability Tests for Printed Boards"

Cov txheej txheem rau kev soj ntsuam xyuas ntawm qhov liab qab PCB nto tiav (HASL, ENIG, OSP, immersion silver, immersion tin, thiab lwm yam).

IPC-A-610 "Kev lees txais ntawm Cov Khoom Siv Hluav Taws Xob"

Muab cov lus piav qhia dav dav rau kev txiav txim siab seb cov pob qij txha thiab cov khoom sib dhos puas tau txais. Qhov no yog qhov feem ntau siv pom kev soj ntsuam cov qauv siv.

Kev Tswj Xyuas Zoo

Incoming Quality Control (IQC)

Solder: Tshuaj ntsuam xyuas muaj pes tsawg leeg, kev txiav txim siab melting point

Flux: Tus nqi ntawm cov kua qaub, cov ntsiab lus khib nyiab, kev kuaj cov ntsiab lus halogen

Cheebtsam: Solderability sampling, plating thickness ntsuas

Hauv -Kev Tswj Xyuas Txheej Txheem Zoo (IPQC)

Solder paste printing: Thickness, txoj hauj lwm offset, bridging nrhiav kom tau (SPI khoom)

Reflow profile: tiag -lub sijhawm ntsuas kub, ncov / TAL kaw

Wave soldering: Solder kub, conveyor ceev, dross kom muaj nuj nqis xyuas

Kev Tswj Xyuas Qhov Kawg (FQC)

Tsis Siv Neeg Optical Inspection (AOI): Txheeb xyuas qhov tsis xws luag xws li cov pob qij txha txias, kev sib txuas, thiab cov khoom siv tsis txaus

X-Ray Inspection: Tshawb xyuas cov voids thiab kev sib txuas hauv cov pob qij txha zais ntawm BGAs, QFNs, thiab lwm yam.

Kev Ntsuas Hluav Taws Xob: Qhib / luv, impedance, ua haujlwm pov thawj

Solder Alloy Xaiv Qhov Kev Txiav Txim Siab

Application Scenario Analysis

Xaiv cov hlau alloys yuav tsum tau ua ntej kom meej meej cov khoom siv cov xwm txheej thiab cov kev xav tau ntawm kev ntseeg tau:

Consumer Electronics (Smartphones, Tablets, Wearables)

Cov kev txhawj xeeb tseem ceeb: Kev cuam tshuam kev ua haujlwm, kev tswj tus nqi

Pom zoo alloys: SAC105, SAC0307, ​​los yog qis -silver doped SAC

Flux: Tsis yog- hom huv

Cov Khoom Siv Hluav Taws Xob / Kev Sib Txuas Lus

Cov kev txhawj xeeb tseem ceeb: Kev cia siab ntawm kev siv cua sov, kev ruaj ntseg ntev -

Pom zoo alloys: SAC305, SAC387

Flux: Tsis yog- huv lossis dej- soluble (nrog tu)

Automotive Electronics

Cov kev txhawj xeeb tseem ceeb: Dav kub ntau (-40℃rau +150 degree), kev co durability

Pom zoo alloys: SAC305 / SAC387; xav txog siab -kub alloys rau qhov chaw cav compartment

Cov cai tshwj xeeb: AEC-Q100/Q200 ntawv pov thawj

Aerospace / Tub rog

Cov kev txhawj xeeb tseem ceeb: Kev ntseeg siab heev, tin whisker pheej hmoo, lub neej ua haujlwm ntev

Cov alloys pom zoo: Tej zaum yuav raug zam kom siv cov tin - txhuas (Sn63/Pb37), los yog cov ntawv pov thawj nruj heev - cov tshuaj dawb

Cov cai tshwj xeeb: NASA, ESA, MIL-STD ua raws

Cov cuab yeej kho mob

Cov kev txhawj xeeb tseem ceeb: Biocompatibility, ntev -kev cia siab rau lub sij hawm, kev tswj hwm

Cov alloys pom zoo: SAC305 (cov khoom siv cog tau tuaj yeem siv cov tin - zam kev zam)

Cov cai tshwj xeeb: FDA, ISO 13485 ntawv pov thawj

Tsawg-Temperature Assembly

Cov kev txhawj xeeb tseem ceeb: txo qhov kev puas tsuaj thermal, kev tiv thaiv warpage

Pom zoo alloys: Sn{0}}Bi series (Sn42Bi58, Sn42Bi57Ag1)

Kev txiav txim siab: Ntsuam xyuas seb lub zog ntawm lub tshuab ua tau raws li qhov xav tau ntawm daim ntawv thov

Comprehensive Evaluation Matrix

Hauv kev xaiv cov tswv yim, cov qhab nia muaj peev xwm ua tau thoob plaws hauv qab no:

Supply Chain thiab cov nqi txiav txim siab

Nyiaj Nqe Volatility Risk

Cov nqi nyiaj tuaj yeem suav txog 60-70% ntawm SAC alloy cov nqi. Thaum cov nqi nyiaj hloov pauv hloov pauv ntau, cov nqi solder hloov raws li. Cov lus pom zoo:

Kos npe rau daim ntawv cog lus nrog tus neeg xa khoom

Ntsuam xyuas qhov ua tau ntawm qhov qis- nyiaj hloov pauv

Tsim kom muaj cov khoom lag luam tsim nyog

Muab ntawv pov thawj

Cov ntawv thov tseem ceeb yuav tsum tsim kom muaj Cov Npe Muag Khoom Pom Zoo (AVL), xav kom cov neeg xa khoom muab:

Cov ntaub ntawv ua raws li cov ntaub ntawv (RoHS, REACH, cov ntxhia tsis sib haum)

Certificate of Analysis (CoA)

Batch traceability muaj peev xwm

Solderability test reports

Yav Tom Ntej Trends thiab Technology Outlook

Soldering Challenges nyob rau hauv Advanced Ntim

Raws li cov ntim ntim ntim hloov mus rau 2.5D / 3D kev koom ua ke, cov cuab yeej siv hluav taws xob ntsib teeb meem tshiab:

Microbumps

Copper pillar microbump suab nyob rau hauv cov ntim siab tau poob qis rau hauv qab 40 micrometers, nrog rau cov txheej tuab ntawm tsuas yog ob peb micrometers. Xws li cov khoom me me ua kom muaj kev cuam tshuam ntawm IMC txoj kev loj hlob ntawm kev ntseeg tau, yuav tsum muaj ntau yam muaj pes tsawg leeg thiab kev tswj cov txheej txheem.

Hybrid Bonding

Qee qhov kev ntim khoom siab tau pib siv tooj liab - mus rau - tooj liab ncaj qha kev sib txuas, tshem tawm tag nrho cov solder. Qhov no tej zaum yuav yog qhov kev daws teeb meem zoo tshaj plaws rau ultra- siab- kev sib txuas ceev ceev, tab sis cov nqi tam sim no txwv tsis pub siv, txwv kev siv rau siab - kawg daim ntawv thov.

Evolution of Low-Tsuas Kub Soldering Technology

Tsawg- qhov kub thiab txias tsis yog tsuas yog qhov yuav tsum tau ua rau cov cua sov- cov khoom rhiab heev tab sis kuj yog ib qho tseem ceeb rau kev txuag hluav taws xob thiab txo cov pa tawm. Cov lus qhia tshawb fawb muaj xws li:

Hloov kho Sn-Bi alloys: Overcoming brittleness los ntawm micro-alloying, nano-reinforcement, thiab lwm yam

Transient Liquid Phase (TLP) kev sib txuas: Siv qis- melting- taw tes nruab nrab txheej rau qis- qhov kub thiab txias sib txuas, tom qab tsim siab - melting- taw tes intermetallic compounds

Conductive adhesives hloov solder: Silver-raws li conductive adhesives hloov ib txwm solder nyob rau hauv qee daim ntawv thov

Sustainability Considerations

Ib puag ncig siab ntawm kev lag luam hluav taws xob tsim hluav taws xob txuas ntxiv mus ntxiv:

Kev ntsuas lub neej (LCA): Kev cuam tshuam ib puag ncig ntawm solder txuas ntxiv los ntawm kev rho tawm cov khoom raw mus rau cov khoom kawg - ntawm - lub neej rov ua dua tshiab

Circular Economy: Rov qab thiab rov siv dua cov hlau hlau los ntawm cov khoom siv hluav taws xob pov tseg

Kev Txhim Kho Hluav Taws Xob: Tsawg-kub soldering txo qis reflow qhov cub siv zog

Txawm hais tias tin solder alloys ua ib feem me me ntawm cov khoom siv hluav taws xob, lawv dais lub luag haujlwm ntawm kev txuas tag nrho lub ntiaj teb hluav taws xob. Los ntawm classic tin -lead eutectic mus rau complex multi-element lead-dawb alloys, los ntawm yooj yim compositional piv rau meej microstructure tswj, txhua yam ua ntej nyob rau hauv solder science tau tsav electronics manufacturing mus rau siab dua kev ntseeg, me me qhov ntev, thiab cov nqi qis dua.

Hauv kev coj noj coj ua- lub sijhawm pub dawb, SAC305 tau dhau los ua kev lag luam tseem ceeb vim nws qhov kev ua tau zoo tag nrho; tab sis tsis muaj ib qho txhuas tuaj yeem ua tau raws li txhua daim ntawv thov. Cov engineers yuav tsum nkag siab tob txog cov yam ntxwv ntawm cov alloys sib txawv thiab txiav txim siab xaiv kev tshawb fawb raws li cov kev cai tshwj xeeb ntawm kev thov kev ntseeg siab, cov txheej txheem txwv, thiab cov hom phiaj ntawm tus nqi.

Saib mus rau lub neej yav tom ntej, raws li kev ntim khoom siv thev naus laus zis txhim kho thiab kev ruaj ntseg yuav tsum tau nce, solder technology yuav txuas ntxiv mus. Tab sis txawm hais tias kev hloov pauv thev naus laus zis li cas, lub hom phiaj tseem ceeb ntawm kev nrhiav kev sib txuas kom ntseeg tau yuav tsis hloov pauv -vim qhov kev ntseeg siab ntawm txhua qhov sib koom ua ke cuam tshuam nrog lub neej ntawm tag nrho cov tshuab hluav taws xob.