I-Fiducial Marks ku-PCB: Idizayini ephelele & Umhlahlandlela Wokubeka

Isingeniso

Izimpawu ze-Fiducial mancane, izindawo eziyireferensi zethusi eziveziwe ku-PCB ezisetshenziswa amasistimu okubona ngomshini ukuqondisa amabhodi ngesikhathi sokubekwa kwe-SMT. Ngaphandle kwemininingwane enembile, imishini yokukhetha nendawo ayikwazi ukunxephezela ukwelulwa kwebhodi, amaphutha okuzungeza, noma ukukhukhuleka okwethulwe ngesikhathi sokwenziwa. Lo mhlahlandlela uchaza ukuthi kungani amamaki e-fiducial ebalulekile, osayizi abanconyiwe kanye nokucaciswa, kanye nemithetho yesakhiwo esisebenzayo enciphisa amaphutha okubeka nokusebenza kabusha.

Iyini I-Fiducial Mark?

Uphawu lwe-fiducial luyisiyingi, iphedi yethusi eveziwe ezungezwe indawo yemvume yemaski ye-soda engavinjelwe. Isixhumanisi esibonakalayo esinomehluko omkhulu phakathi kwethusi elingenalutho kanye nemaski sinika amandla amasistimu okubona amehlo ukuze asungule izixhumanisi ze-XY ezinembile. Amakhamera abona ngomshini asebenzisa amamaki e-fiducial ukuze abale i-offset yebhodi, ukuzungezisa, nokuhlanekezela kwesikali ngaphambi kokubeka izingxenye.

Imisebenzi Eyisisekelo Yamamaki Atholakalayo

Ama-fiducial asebenza imisebenzi emithathu ebalulekile yokuqondanisa: ukulungiswa kwesikhundla (ukukhokhela ukuhlukahluka kwephaneli kuya kwephaneli), ukulungiswa kokujikeleza (ukulungisa ukungalingani kwe-angular ngesikhathi sokulayisha ibhodi), kanye nokubuyiselwa kwesikali (okubalwa izinguquko zobukhulu ezivela ekucindezelekeni kokushisa noma komshini ngesikhathi sokubopha).

Izinhlobo Zamamaki E-Fiducial Nezicelo Zawo

Global Fiducials

Amamaki e-Global fiducial ahlinzeka ngamaphoyinti ereferensi ebhodi lonke. Zibekwe ezindaweni ezintathu ezingezona i-collinear (imvamisa kuphethini engunxantathu), zinika amandla umshini wokubeka ukubala indawo, ukuzungezisa, nokukala ngesikhathi esisodwa. Yonke i-PCB edinga ukuhlanganiswa okuzenzakalelayo kufanele ifake okungenani ama-fiducials amabili omhlaba, nakuba okuthathu kunconywa kakhulu.

I-Fiducials yendawo

Amamaki endawo abekwe eduze kwezingxenye zephimbo elihle njengama-BGA nama-QFP anezikhala zomthofu ezingaphansi kuka-0.5 mm. Lokhu kunikeza ukulungiswa kwendawo okungaphezu kwalokho okungafinyelelwa yi-fiducials yomhlaba wonke, ukubala i-warpage ye-micro-scale noma ukunwebeka ezindaweni eziminyana kakhulu. Engeza ama-fiducials asendaweni lapho ukuphakama kwengxenye yehla ngaphansi kuka-0.5 mm noma ububanzi bebhola bungaphansi kuka-0.3 mm.

I-Panel Fiducials

Amamaki ephaneli efiducial akhona ezingeni lamalungu afanayo kuneleveli yebhodi ngayinye. Imiswe kojantshi abaphukayo noma amakhona amaphaneli, iqondisa kokubili ukubekwa kwe-SMT nokokusebenza kokuhlukanisa. I-Panel fiducials iqinisekisa ukubhaliswa okungaguquguquki kuwo wonke amabhodi ohlwini phakathi kokubili kwezinqubo zokuhlanganisa nokuhlukanisa.

Amapharamitha Wokuklama Abalulekile Namagugu Anconyiwe

Ubukhulu obufanelekile bamaki we-fiducial buthinta ngokuqondile ukuthembeka kokuqashelwa. Ithebula elingezansi lifingqa ukucaciswa okwamukelwe yimboni:

Kungani Lezi Zimiso Zibalulekile

Isilinganiso sokuvunyelwa kwemaski siqinisekisa umehluko owanele phakathi kwethusi ne-laminate ezungezile. Uma imvume ingaphansi kuka-2× irediyasi ye-fiducial, ukulandelelwa okuseduze noma imiphetho yemaski ingase iphazamise ama-algorithms okuthola unqenqema. Ukucaciswa konqenqema okungu-3.35 mm kuthwala izindawo zamathuluzi emishini futhi kuvimbele ukuthi ama-fiducials angalinyazwa ngesikhathi sokuhlukaniswa.

Imithetho yokubeka uphawu lwe-Fiducial kanye Nemikhuba Engcono Kakhulu

Ukubekwa kwe-Global Fiducial

Misa amamaki e-fiducial emhlabeni wonke emakhoneni amathathu e-PCB, enze unxantathu ongena-asymmetric. Gwema ukubeka ama-fiducials kumathebhu asheshayo, eduze nezimbobo eziqhekeziwe, noma ngaphakathi kwezindawo zokulungisa imishini. Ukuhlukaniswa okuphezulu phakathi kwama-fiducials kuthuthukisa ukulungiswa kwe-angular yesinxephezelo sokuzungezisa.

Ukubekwa Kwendawo Yendawo

Beka amamaki endawo phakathi kuka-5 mm wamaphedi wengxenye ye-fine-pitch, nezindawo ezicacile ezingenayo ithusi, isikrini sikasilika, noma izici zemaski edayiswa. Kuma-BGA, beka ama-fiducial amabili endawo emakhoneni abhekene ngokudayagonali. Gcina okungenani ibanga eligcwele lendawo yokusula kusukela kunoma yisiphi isici sethusi esiseduze.

Iphaneli Fiducial Ukubekwa

Amamaki ephaneli afiducial kufanele avele kuwo wonke amakhona ohlaka lwamalungu afanayo noma kumareyili aphikisayo. Uma usebenzisa ama-rails aphukayo, beka ama-fiducials okungenani ama-5 mm ukusuka kunoma iyiphi i-V-score noma unqenqema oluzungezwe ithebhu. Qinisekisa ukuthi ibhodi elincane ngalinye ligcina ukufinyelela kuma-fiducials alo noma ama-fiducials ephaneli okwabelwana ngawo kuyo yonke inqubo yomhlangano.

Izindawo Zokugwema

Gcina amamaki e-fiducial ekude nezimbobo zamathuluzi, izimbobo ezikhuphukayo, ama-V-grooves, nanoma yisiphi isifunda esingaphansi kwengcindezi yokusebenza ngesikhathi sokuphatha. Ungabeki ama-fiducials ezindaweni ezizosuswa ngesikhathi sokuhlukaniswa.

Ukukhiqiza kanye Nokucatshangelwa Komhlangano

Izidingo Zokuqeda Ubuso

Amamaki e-fiducial adinga ukuqedwa kobuso obukhanyayo okuphezulu ukuze kubonwe ikhamera kahle. I-HASL, i-ENIG, kanye ne-infusion tin konke kunikeza umehluko owanele. Ukuqedwa kwe-OSP kuyasebenza kodwa kungabonisa amazinga okuqashelwa aphansi uma kwenzeka i-oxidation. Qinisekisa ukuthi ukujiya kokuqeda kuhlala kufana kuzo zonke i-fiducials—ukwehluka okungaphezu kwama-5 μm kungathinta incazelo yomphetho.

I-Solder Mask kanye nokusebenzisana kwe-stencil

Izimpawu ze-fiducial kumele zihlale zingenawo nhlobo ukumbozwa kwemaski ye-solder. Chaza ama-fiducials njengokuvuleka kwemaski ye-solder kulabhulali yakho ye-CAD ukuze uvimbele ukufakwa ngengozi. Izimbobo zestencil kufanele zingafaki izindawo ze-fiducial ngokuphelele-namathisela amadiphozithi kuma-fiducials alulaza ukunemba kokuqashelwa.

Ukuxazulula Ukuhluleka Kwesistimu Yombono

Ukungaphumeleli kokubonwa okuvamile kuvela ekungcoleni (izinsalela ezigelezayo, amafutha okuphatha), ukufakwa kwe-oxidation (ikakhulukazi ekuqedeni kwe-OSP), imiphetho yemaski engahambisani (izimbobo ezimangelengele noma ezingaqondani kahle), kanye nokufakwa okungeyona into efanayo. Hlola ama-fiducials ngaphansi kokukhulisa uma imishini yokubeka ibika amaphutha okuqondanisa aphindaphindiwe. Hlanza amabhodi nge-IPA uma kusolwa ukungcola.

Iphaneli Fiducial Mark Ukucatshangelwa

Ukugcinwa kwe-Sub-Board Fiducial

Uma ufaka amaphaneli , qinisekisa ukuthi ibhodi elincane ngalinye ligcina amamaki okuthembeka asebenzayo ngemva kokususwa kwamaphaneli. Uma ukwakheka kwephaneli kususa ama-fiducial ebhodi okuqala nge-rail ephukile, engeza ama-fiducial angafuneki ngaphakathi kohlaka lwebhodi azosinda ekuhlukaneni.

Izidingo eziqondene nomkhiqizi

Panel fiducial locations, rail dimensions and any marks needed after depaneling should be agreed with the surface-mount assembly provider before the panel is released. The approved panel drawing should distinguish rail fiducials from the marks that must remain on each finished board.

Amaphutha Ophawu Olujwayelekile Olufingqiwe

Iphutha 1: I-Fiducials Engalinganiselwe Kancane noma Efihliwe

Ama-Fiducials amancane kuno-0.8 mm noma ambozwe kancane imaski ye-solder ahluleka ukubonwa. Amasistimu okubona adinga ubuncane bezibalo zamaphikseli ukuze kutholwe umphetho othembekile. Njalo qinisekisa ukuvuleka kwemaski kokuphumayo kwe-Gerber ngaphambi kokukhishwa kokwenziwa.

Iphutha lesi-2: Ukwephulwa kwe-Edge Proximity

I-Fiducials ebekwe phakathi kuka-3 mm webhodi elinqenqemeni lokulimala kusuka kumabhithi omzila noma ama-V-score blades. Leli phutha livamise ukuvela lapho amabhodi eshintshwa usayizi sekwephuzile emjikelezweni wokuklama ngaphandle kokumiswa kabusha ngendlela efiselekayo.

Iphutha 3: Ubukhulu obungahambisani

Ukuhlanganisa amadayamitha e-fiducial (isb, 1.0 mm global no-1.5 mm wendawo) kudida ama-algorithms afana nephethini. Gcina izilinganiso ezifanayo zawo wonke amamaki e-fiducial ebhodini elilodwa noma iphaneli.

Iphutha 4: Ukwephulwa Kwendawo Yokusula

Umbhalo wesikrini sikasilika, amalogo, noma ukulandelela umzila ngaphakathi kwendawo yokususa imaski kwehlisa ukugqama komphetho. Imithetho yedizayini kufanele iphoqelele ukwephulwa kwemvume njengamaphutha e-DRC.

Iphutha 5: Ukulimala Kokuhlukaniswa Kwephaneli

I-Fiducials emi ekuxhumekeni noma eduze komzila wethebhu ingase yonakaliswe ngesikhathi sokuhlukaniswa. Qinisekisa ukusinda kwe-fiducial ngemva kokuhlukana ngokubuyekeza izindlela zephaneli zomzila.

I-DRC kanye Nohlu Lokuhlola Idizayini Yama-Fiducial Marks

Isethi yemithetho ye-DRC esebenzayo isiza ukuqinisekisa ukuthi izimpawu zakho ezithembekile zihlala zikhiqizwa futhi ziyafundeka ngomshini:

• Ububanzi be-fiducial kumele bube ngu-1.0–3.0 mm , kanye nokubekezelelana kobubanzi obungaphakathi kwebhodi ≤ 25 μm.

• Ukususwa kwemaski ye-solder kumele okungenani kube yi-2 × irediyasi ye-fiducial.

• Ibanga elincane ukusuka esikhungweni se-fiducial kuya onqenqemeni lwe-PCB (kufaka phakathi indawo yokuvula) kumele libe ngu-≥ 3.35 mm.

• I-PCB ngayinye kumele ifake okungenani ama-fiducial amabili omhlaba wonke , kuyilapho amathathu enikeza ukuqondanisa okuqinile.

• Ama-fiducial endawo ayadingeka ngaphakathi kwama -5 mm kunoma iyiphi ingxenye ene -pitch < 0.5 mm.

• Azikho izici zemaski zethusi, ze-silkscreen, noma ze-solder ezingavela ngaphakathi kwendawo yokuvula.

Ukusebenzisa lezi zindlela kuzilungiselelo zakho ze-EDA DRC kuqinisekisa ukusebenza kokulungiswa kwe-PCB okuqhubekayo ngesikhathi sokuhlanganiswa kwe-SMT.

Case Studies

Ukuqaliswa Okuyimpumelelo

Ibhodi elilawulayo elinezendlalelo ezine lokuzenzakalela kwemboni lifaka phakathi okutholwe emhlabeni jikelele okungu-1.0 mm kuphethini ye-L kanye nezazi ezimbili zasendaweni eziseduze ne-0.4 mm pitch BGA. Isivuno sokuqala seqe ama-99.7% kumayunithi ayi-10,000. Idizayini inikeze imvume yemaski engu-3.0 mm futhi igcinwe isikhala sonqenqema esingu-4.0 mm—inikeza umkhawulo ongaphezu kwezimfuneko eziyisisekelo.

Ukuhlaziya Ukwehluleka

Ukuqaliswa kwe-prototype kwedivayisi ye-IoT yomthengi kuhlangabezane nokwenqatshwa kokubekwa okungu-15% ngenxa yokungaphumeleli kokubonwa kwe-fiducial. Uphenyo lwembule ama-fiducials angu-0.8 mm anemvume yerediyasi engu-1.5× kuphela, ehlanganiswe nokuqedwa kwe-OSP okwakufakwe i-oxid ngesikhathi sokulondoloza. I-Respin nge-fiducials engu-1.0 mm, ukuqedwa kwe-ENIG, nokucaciswa okungu-2.5× kususe wonke amaphutha okubonwa.

Isiphetho

Amamaki e-fiducial ayisisekelo sokunemba kokuhlanganiswa kwe-PCB okuzenzakalelayo . Ukusetshenziswa okufanele kudinga ukunakwa ekukhethweni kobubanzi, izilinganiso zokususwa, i-geometry yokubekwa, kanye nokuvumelana kokuphela kobuso. Ukutshala isikhathi ekwakhiweni kwe-fiducial okulungile kuvimbela ukulungiswa kabusha okubizayo kanye nokulahlekelwa kwesivuno. Kumaqembu onjiniyela afuna ukwenziwa nokuhlanganiswa okuthembekile, imininingwane ye-fiducial eqinisekisiwe kufanele ibe yingxenye yazo zonke izinhla zokuhlola zokuklama.

imibuzo ejwayelekile ukubuzwa

Ingabe ngidinga amamaki e-fiducial kumabhodi anohlangothi olulodwa?
Yebo. Ngisho namabhodi anohlangothi olulodwa azuza kumamaki e-fiducial uma kusetshenziswa ukubekwa kwe-SMT okuzenzakalelayo. Ngaphandle kwama-fiducials, imishini ithembele kuphela ekutholeni unqenqema lwebhodi, okwethula ukungaqiniseki okukhulu kwendawo.

Imuphi usayizi we-fiducial okufanele ngiwusebenzise ku-0.5 mm pitch BGA?
Sebenzisa ama-fiducials obubanzi obungu-1.0 mm okungenani nokuvunyelwa kwemaski engaba ngu-2×. Engeza ama-fiducials amabili endawo emakhoneni ayi-diagonal we-footprint ye-BGA ngaphezu kwama-fiducials akho omhlaba.

Iphaneli idinga ama-fiducials amangaki?
Amaphaneli kufanele afake ama-fiducials okungenani amakhona amabili aphikisanayo ohlaka, nakuba kukhethwa ukubekwa kwamakhona amane. Ibhodi elincane ngalinye kufanele futhi ligcine ezalo i-fiducials emhlabeni wonke ngemva kokuhlukaniswa.

Ingabe isikrini sikasilika singasetshenziswa njenge-fiducial?
Cha. I-Silkscreen ayinakho ukukhanya nokunemba kobukhulu obudingekayo ukuze ubone umshini. Ithusi eliveziwe kuphela elinendawo efanelekile yokuqeda linikeza ukuqashelwa okuthembekile.

Yini ebangela ukwehluleka kokuqashelwa kwe-fiducial?
Izimbangela ezijwayelekile zifaka i-oxidation, ukungcoliswa, izindawo zokucaciswa ezincane, ukungena kwe-mask, kanye nogqinsi lwe-plating olungahambisani. Hlanza amabhodi futhi uqinisekise ukuvuleka kwemaski uma kwenzeka ukwehluleka.