Kungani Kufanele Usebenzise Igolide Kunesiliva Nethusi Ekwenziweni Kwe-PCB?

Amabhodi esekethe aphrintiwe (ama-PCB) akha umgogodla we-elekthronikhi, ahlinzeka ngosekelo lwemishini kanye nokuxhumana kukagesi phakathi kwezingxenye. Amaphedi nemikhondo kuma-PCB ngokuvamile enziwa ngethusi, elikhipha i-oxidize kalula lapho livezwa emoyeni. Lokhu oxidation kungaphazamisa solderability kanye nokusebenza kukagesi. Ngakho-ke, ama-surface finishes njengegolide, isiliva noma i-organic coatings asetshenziswa ukuvikela ithusi ekugqwaleni.

Lesi sihloko sihlola isizathu sokusebenzisa i-plating yegolide ebizayo uma kuqhathaniswa nesiliva elishibhile noma ithusi ekwenzeni i-PCB.

Uhlolojikelele lwe-Common PCB Surface Finishes

Imikhondo yethusi edaluliwe kuma-PCB igcwele izimbotshana zensimbi noma amafilimu ezinto eziphilayo ukuze kuvinjelwe i-oxidation. Iziqephu ezidumile ze-metallic surface zihlanganisa:

• Isiliva lokucwiliswa - Inqubo ye-Chemical silver plating
• I-Organic solderability preservatives (OSP) - Amafilimu e-Organic okuvikela
• Electrolytic nickel/igolide – Electroplated nickel ngaphansi kwegolide
• I-Nickel engenawo ugesi/igolide lokucwiliswa (ENIG) - I-nickel engenawo amandla bese kucwiliswa igolide

Kulokhu, i-ENIG kanye ne-electrolytic nickel/igolide zisebenzisa igolide ukukhulisa ukumelana nokugqwala kanye nokusebenza kahle. Kodwa igolide libuye libe isiphetho esibiza kakhulu.

Isidingo Sokuqeda Ubuso Kuma-PCB

Ama-PCB asebenza njengenkundla yokukhweza nokuxhumanisa izingxenye ze-elekthronikhi. Imikhondo yethusi eqoshwe kuma-PCB ihlinzeka ngemikhondo ye-conductive yamasignali namandla.

Kodwa-ke, i-copper yenza kalula i-non-conductive copper oxide lapho ibhekene nomoya-mpilo kanye nomswakama. Lokhu kufakwa kwe-oxidation kungase kuqale ngesikhathi sokwenziwa kwe-PCB ngokwayo lapho ikhopha ivezwa.

Inqubo ye-oxidation iyaqhubeka njengoba ithusi elingenalutho lishiywa livezwa ezindaweni ezizungezile. Lokhu kuyiqiniso ikakhulukazi kuma-soldering pads adinga ukudayiswa kamuva ukuze anamathisele izingxenye. Ukwakheka kwe-oxide kumaphedi kunciphisa ukudaleka.

Ngaphezu kwalokho, i-oxidation ikhulisa ukumelana nogesi, okuphazamisa ukuxhumana kukagesi. Amalunga e-solder angalungile ngenxa yalokho angabangela ukwehluleka kwedivayisi noma ukunciphisa ukuthembeka.

Ngakho-ke, ukuqedwa kwe-PCB surface kunikeza imisebenzi eminingi:

• Vimbela i-copper oxidation ngaphambi kokuhlanganisa
• Nika amandla ukwakheka okuhlangene kwe-solder okuthembekile
• Gcina ukumelana okuphansi kokuxhumana emalungeni
• Vikela ithusi ekugqwaleni ngesikhathi sokuphila komkhiqizo

Kungani Igolide Lisetshenziswa Ekwenziweni Kwe-PCB

Igolide linikeza izinzuzo ezihlukile eziyenza ibe insimbi yokuzikhethela kokuqedwa kwe-PCB ngaphezulu ezinhlelweni eziningi:

Ukumelana Nokugqwala Okuhle kakhulu

Igolide alisebenzi kakhulu futhi alikhihlisi noma aligqwali ngaphansi kwezimo zokusetshenziswa ezijwayelekile noma izindawo ezizungezile. Lokhu kulondoloza ukuhlanzeka kanye nokusebenza kwemikhondo efakwe ngegolide phakathi namashumi eminyaka yokuphila komkhiqizo.

High Electrical Conductivity

Igolide linesilinganiso esiphezulu sokusebenza kukagesi ngemva kwesiliva nethusi. Kodwa kokubili isiliva nethusi kujwayele ukugqwala phezulu. I-conductivity yegolide enhle kakhulu ihlangana nokumelana nokugqwala kwayo.

Izinketho Zokumisa Eziguquguqukayo

Izingubo zegolide zingasetshenziswa kalula kuma-PCB ngezinqubo ezifana ne-electroless noma i-electrolytic plating. Ubukhulu bungalawuleka njengoba kudingeka.

I-Solderability evelele

Igolide livumela ukwakheka kwamajoyinti e-solder athembeke kakhulu ngaphandle kwezinkinga zokumanzisa. I-solderability ihlala iqinile phakathi nezikhathi zokulondoloza.

Impilo Yesikhathi Eside

Igolide ligcina ubumsulwa kanye nezakhiwo zalo ngokungapheli. Lokhu kuvumela izimpilo zeshalofu ezinde kakhulu kuma-PCB afakwe ngegolide.

Ama-Ductile Deposits

Igolide lihlinzeka ngama-ductile coatings athambekele kancane ekuqhekekeni noma ekuqhekekeni ngaphansi kwengcindezi yokuhamba ngebhayisikili.

I-Wire Bonding Amandla

Ukuqedwa kwegolide kuvumela ukubopha ngentambo kwesivuno esikhulu, okubalulekile kuma-microelectronics.

Ukusebenza kabusha

Izingubo zegolide zivumela imijikelezo eminingi yokusebenza kabusha nokulungisa ngaphandle kokulahlekelwa ubuqotho bomhlaba noma izakhiwo.

Ukuhambisana Kwamahhala Okuhola

Igolide lihambisana ngokugcwele nama-solder angenawo umthofu kanye nezinqubo zokudambisa.

Okungalungi Kweziqephu Zesiliva Nethusi

Isiliva nethusi kunikeza izinzuzo ezifana ne-conductivity ephezulu kanye nezindleko eziphansi uma kuqhathaniswa nezicwecwe zegolide. Nokho, kokubili isiliva nethusi kunenkinga yokulinganiselwa:

I-Oxidation kanye Nokugqwala: Isiliva nethusi zikhipha oksijini kalula futhi zigqwale ezindaweni ezizungezile. Lokhu kuholela ekwandeni kokumelana nokuxhumana kanye ne-solderability embi ngokuhamba kwesikhathi.

Ukwethenjwa Kwe-Soldering Okubi: Ukwakheka kwe-oxide kuphazamisa ukumanzisa okufanele lapho kufakwa i-solder. Ukuxhumana kwensimbi okungafani nama-solder nakho kwandisa ubungozi bokuhluleka.

Impilo Yeshelufu Encishisiwe: Imithelela ye-oxidation kanye nokugqwala endaweni yesiliva neyethusi iqala ngokushesha ngemuva kokucwetshwa. Lokhu kudinga i-soldering ngokushesha ngemva kokucwenga.

I-Inferior Wire Bonding: Izingozi ze-oxidation zenza izinselele zokuhlanganisa izintambo ngesiliva/ithusi uma kuqhathaniswa negolide.

Ukuthembeka Kokuhamba Ngebhayisikili Okushisayo: Ama-oxide esiliva nawethusi athambekele ekulimaleni ngaphansi kokuguquguquka kwezinga lokushisa uma kuqhathaniswa negolide le-ductile.

Izithiyo Zemvelo: Ukungcoliswa kwezingubo zesiliva kungakhulula izinhlanganisela zesiliva ezinobuthi endaweni ezungezile ngesikhathi sokusetshenziswa nokulahlwa.

Izindleko Eziphakeme Zomjikelezo Wokuphila: Izinkinga ezivamile zokugqwala kanye ne-solder ngezindawo zesiliva/zethusi zihumushela ekulungiseni okuphezulu, ekusetshenzisweni kabusha nasezindlekweni zewaranti.

PCB Surface finish Izinqubo Zegolide

I-Electroless Nickel Immersion Gold (ENIG)

I-Electroless Nickel Immersion Gold (ENIG) iyindawo engaphezulu esetshenziswa kabanzi yamabhodi esekethe aphrintiwe (PCBs). Iqukethe inqubo enezinyathelo ezimbili ezibandakanya ukubekwa kwezingqimba ze-nickel nezegolide emikhondweni yethusi ye-PCB. Nakhu ukuhlukaniswa kwenqubo ye-ENIG nezici zayo ezibalulekile:

I-Electroless Nickel Plating

• Esinyathelweni sokuqala, imikhondo yethusi ye-PCB icwiliswa kubhavu wamakhemikhali oqukethe isixazululo sikasawoti we-nickel, ama-reduction agents, kanye nezinzinzisi.
• Ama-nickel ions esixazululweni ancishiswa ngendlela emangalisayo endaweni yethusi, enze ungqimba olufana noluqhubekayo lwe-nickel engenawo ugesi.
• Ugqinsi longqimba lwe-nickel ngokuvamile lusukela ku-3-6 μm (ama-micrometer). Lokhu ukujiya kunikeza ukumboza okuhle futhi kusebenza njengesithiyo sokusabalalisa phakathi kwezingqimba zethusi nezegolide.

Ukucwiliswa Igolide Deposition

• Ngemva kokufakwa kwe-nickel, i-PCB ibe isicwiliswa esixazululweni esiqukethe usawoti wegolide.
• Ama-ion egolide ekhambi ancishiswa ngamakhemikhali, afake ungqimba oluncane lwegolide endaweni ye-nickel ngokusebenzisa inqubo yokucwiliswa.
• Ungqimba lwegolide luvamise ukuba nogqinsi olusuka ku-0.03-0.15 μm, luhlinzeka ngembongolo evikelayo emincane kodwa ephumelelayo.

Izici Ezisemqoka kanye Nezinzuzo ze-ENIG

1. Isithiyo Sokusabalalisa: Isendlalelo se-nickel sisebenza njengesithiyo sokusabalalisa, esivimbela ukufuduka kwethusi kungqimba lwegolide futhi ngokuphambene nalokho. Lesi sithiyo sisiza ukugcina ubuqotho besendlalelo segolide futhi sivimbele ukwakheka kwezinhlanganisela ze-intermetallic ezingase zibe nomthelela ekuthembekeni kwe-solder joint.
2. I-Solderability: I-ENIG inikeza ukuthengiselana okuhle kakhulu ngenxa yendawo yegolide eyisicaba futhi ebushelelezi. Ungqimba lwegolide lusiza ukumanziswa kwe-solder phakathi nenqubo yokuhlanganisa, iqinisekisa amalunga athembekile e-solder.
3. Ukuvikela Ukugqwala: Igolide limelana kakhulu ne-oxidation kanye nokugqwala, linikeza ungqimba oluthembekile lokuvikela lwe-nickel engaphansi nethusi. Lokhu kumelana nokugqwala kubaluleke kakhulu kuma-PCB asetshenziswa ezindaweni ezinokhahlo noma achayeke kumswakama.
4. I-Surface Flatness: Inqubo ye-ENIG iphumela endaweni eyisicaba futhi eplaniwe, ebalulekile ezingxenyeni ze-fine-pitch surface mount technology (SMT). Indawo yegolide ebushelelezi isiza ukuqinisekisa ukubekwa kwengxenye okunembile nokuxhumeka okuthembekile kwe-solder.
5. Ukusebenza Okuhle Kokagesi: I-ENIG inokuhamba kahle kukagesi kanye nokumelana nokuxhumana okuphansi, okuyenza ifanelekele izinhlelo zokusebenza zedijithali ezinemvamisa ephezulu kanye nesivinini esikhulu.
6. Ukuvumelana Kokubopha Ngocingo: Ungqimba lwegolide ku-ENIG luhambisana nezindlela zokuhlanganisa izintambo ezisetshenziselwa ukuxhuma ama-semiconductor chips ku-PCB. Indawo yegolide ebushelelezi isiza ukuxhuma okuthembekile kwezintambo.

Sekukonke, i-Electroless Nickel Immersion Gold (ENIG) inikezela ngokuphela okuthembekile nokuguquguqukayo kwendawo yama-PCB, ihlinzeka ngokuthengiswa okuhle kakhulu, ukumelana nokugqwala, nokusebenza kukagesi. Ukusetshenziswa kwayo kugcwele ezimbonini ezahlukahlukene, kufaka phakathi ugesi othengwayo, ezokuxhumana, i-aerospace, kanye nemishini yezokwelapha.

Izici zenqubo ye-Gold-Plated PCBs

Izinkinga ze-Solderability

Nakuba ungqimba lwegolide lwe-plating lubonisa ukuzinza okuhle kwamakhemikhali, lokhu kuzinza futhi kusho ukuthi igolide ayenzi kalula i-alloy enhle nge-solder, ngaleyo ndlela ithinte ikhwalithi yamalungu e-solder.
Ngesikhathi se-solder, uma ungqimba lwegolide lulugqinsi kakhulu, igolide lingase lincibilike ku-solder, okuholela ekuhlanganiseni kwe-brittle solder. Lesi simo saziwa ngokuthi "i-gold embrittlement."

Material, layer construction, holes and surface finish need to be released as one bare-board fabrication scope. A metal’s general conductivity or corrosion behavior does not by itself establish the right finish for every PCB application.

Imikhawulo yokusetshenziswa

Ngenxa yezinkinga ze-solderability, igolide plating ngokuvamile ayisetshenziswa ezindaweni ezidinga kakhulu soldering. Esikhundleni salokho, isetshenziswa kakhulu ezindaweni zokuxhumana zesixhumi noma izindawo ezihloselwe ukuhlanganisa izintambo ze-aluminium.
Ezindaweni lapho ukusoda kuyadingeka khona, ezinye izindlela zokwelapha ezingaphezulu njenge-Organic Solderability Preservatives (OSP), i-solder engenamthofu, noma ama-alloys e-tin-lead avame ukusetshenziswa.

Ukucatshangelwa kobunjiniyela

Lapho uklama i-PCB enegolide elicwebezelayo, kucatshangelwa ngokucophelela ukujiya kongqimba lwegolide kanye nendawo esetshenziswa kuyo ukuze kuqinisekiswe ukuthi izinzuzo zegolide zingasetshenziswa kuyilapho kugwenywa izithiyo zayo ekuhlanganisweni.
Ngakho-ke, naphezu kokusebenza okuphezulu kwama-PCB afakwe ngegolide ezicini ezithile, kukhona ngempela ukulinganiselwa mayelana nokusebenza kwe-solder. Le mikhawulo idinga ukunakwa okukhethekile ngesikhathi sokuklama kanye nenqubo yokukhiqiza.

Izicelo Ezibalulekile zama-PCB Afakwe Ngegolide

Ezinye izibonelo zezinhlelo zokusebenza ezibucayi ezincike kuma-PCB afakwe ngegolide zifaka:

• I-Aerospace kanye ne-Avionics: Ukwethembeka kwegolide kuqinisekisa ukusebenza impilo yonke emisebenzini yasemkhathini.
• Amadivayisi Ezokwelapha: Izingubo zegolide zivimbela ukugqwala kumadivayisi afakiwe kanye nokuxilongwa.
• I-Undersea Electronics: Igolide limelana nezimo ezinomfutho ophezulu kanye nezimo ezinosawoti ezitholakala kumishini ye-oceanographic.
• Izifunda Zedijithali Zesivinini Esiphezulu: Ukusebenza kwegolide kuvumela ukudluliswa kwedatha okunganaphutha kufika kumafrikhwensi e-multi-GHz.
• Amamojula weMicrowave kanye neRadar: Ukufakwa kwegolide kunikeza ukulahlekelwa okuphansi kakhulu kumafrikhwensi ama-microwave.
• Izixhumi Nokudluliswa Kwe-Electromechanical: Igolide eliqinile ezindaweni zokuxhumana liphatha izigidi zemijikelezo yokushintsha.
• I-Photonic/Optoelectronic Systems: Izingubo zegolide zinikeza ukukhanya okuphezulu okudingekayo kumathuluzi okubona anembile.

Isiphetho

Kafushane, igolide liwukuphela kwendawo efanelekile ye-PCB yezinhlelo zokusebenza ezifuna ukuthembeka kokugcina, ukuqhutshwa kwe-conductivity, ukumelana nokugqwala, ukudayiswa kanye nokusebenza kwe-wire bonding. Izindleko eziphakeme zokuqala zegolide zivunyelwa ikhwalithi yomkhiqizo ethuthukisiwe, ubude besikhathi sokuphila, kanye nezingozi ezincishisiwe zokwehluleka ezinhlelweni ezibucayi. Lokhu kwenza igolide lifane nesisindo salo ekunikeni amandla ama-electronics esizukulwane esilandelayo ukuthi aqhubeke nokuphusha imikhawulo yokusebenza nokuqina.

Posts Related

1.Iyini Inqubo Yokukhiqiza I-PCB?
2.Izinzuzo kanye nokubi kwe-PCB surface finish
3. Umhlahlandlela Ophelele we-PCB Surface Finishes: Ukukhethwa, Izakhiwo, kanye Nokucatshangelwa Kokwethenjelwa