Ngaphambi PCB, amasekethe ayenziwe ngezintambo zokukhomba. Ukuthembeka kwale ndlela kuphansi kakhulu, ngoba njengoba iminyaka yesifunda, ukuqhekeka kolayini kuzoholela ekhefini noma isekhethi elifushane lendawo yomugqa. Ukuhamba phambili kusengaphambili kwezobuchwepheshe besifunda, okuthuthukisa ukuqina nokushintshwa kwesifunda ngokufaka ucingo oluncane lobubanzi elizungeze ikholomu endaweni yokuxhuma.

Ngenkathi imboni ye-elekthronikhi isuka kumashubhu we-vacuum futhi idluliselwa kuma-silicon semiconductors namasekhethi ahlanganisiwe, ubukhulu nentengo yezinto zikagesi kwehlile. Ukuba khona njalo kwemikhiqizo kagesi emkhakheni wabathengi sekugqugquzele abakhiqizi ukuthi bafune izixazululo ezincane nezonga imali. Ngakho-ke, i-PCB yazalwa. Inqubo yokukhiqiza ye-PCB iyinkimbinkimbi kakhulu. Ukuthatha i-PCB enezingqimba ezine njengesibonelo, inqubo yokukhiqiza ikakhulu ifaka ukwakheka kwe-PCB, ukukhiqizwa kwebhodi eyinhloko, ukudluliswa kwesakhiwo kwangaphakathi kwe-PCB, ukubhoboza ibhodi okuyisisekelo nokuhlola, ukuvumbulula, ukubhola, imvula yamakhemikhali yethusi yodonga lomgodi, ukudluliswa kokuhlelwa kwe-PCB yangaphandle, i-PCB yangaphandle ukudweba nezinye izinyathelo.

1. Ukuhlelwa kwe-PCB

Isinyathelo sokuqala sokukhiqizwa kwe-PCB ukuhlela nokuhlola ukuhlelwa kwe-PCB. Isitshalo se-PCB bumbela sithola amafayela we-CAD avela enkampanini eyakha i-PCB. Njengoba isoftware ngayinye ye-CAD inefomethi yayo ehlukile yefayela, isitshalo se-PCB siguqula sibe yifomethi ebumbene – iGerber RS-274X enwetshiwe noma iGerber X2. Lapho-ke unjiniyela wefekthri uzohlola ukuthi ngabe ukwakheka kwe-PCB kuvumelana yini nenqubo yokukhiqiza, ukuthi ngabe kukhona ukukhubazeka nezinye izinkinga.

2. Ukukhiqizwa kwamapuleti amancane

Hlanza ipuleti elimbozwe ithusi, uma uthuli lungadala isekhethi lokugcina isekhethi elifushane noma ikhefu. Umdwebo 1 ngumfanekiso we-PCB enezingqimba eziyi-8, empeleni enamacwecwe amathathu agqokwe ngethusi (amabhodi ayisisekelo) kanye namafilimu wethusi ama-3 bese ehlanganiswa namashidi aphulukisiwe. Ukulandelana kokukhiqiza kuqala kusuka ebhodini eliyinhloko (izingqimba ezine noma ezinhlanu zemigqa) phakathi, futhi kuhlanganiswa ngokuqhubekayo ngaphambi kokulungiswa. I-4-layer PCB yenziwe ngokufanayo, kepha inepuleti elilodwa kuphela eliyisisekelo namafilimu amabili wethusi.

3. Yenza umjikelezo webhodi yomgogodla ophakathi nendawo

Ukudluliswa kokuhlelwa kwe-PCB yangaphakathi kufanele kuqala kwenziwe isekhethi engqimba emibili yebhodi leCore eliphakathi kakhulu (Core). Ngemuva kokuhlanzwa kwepuleti eligqokwe ngethusi, ingaphezulu limbozwa ngefilimu ebukekayo. Ifilimu iyaqina lapho ivezwa ukukhanya, yakhe ifilimu evikelayo phezu kocwecwe lwethusi lwensimbi egqitshwe ngethusi. Faka izingqimba ezimbili ze-PCB yesakhiwo sefilimu nezendlalelo ezimbili zebhodi eligqokiwe ithusi, futhi ekugcineni faka ungqimba olungaphezulu lwefilimu yokuhlelwa kwe-PCB ukuqinisekisa ukuthi izingqimba ezingenhla nezaphansi zesakhiwo se-PCB sesakhiwo sokubeka ifilimu sinembile. I-Photosensitizer isebenzisa isibani se-UV ukukhanyisa ifilimu enesithombe esithombeni sethusi. Ifilimu enesithombe iqiniswa ngaphansi kwefilimu esobala, futhi ifilimu ebukekayo ayiqiniswa ngaphansi kwefilimu e-opaque. Ucwecwe lwethusi oluhlanganiswe ifilimu eliqinile le-photosensitive umugqa wesakhiwo se-PCB odingekayo, olingana nendima ye-laser iphrinta inki ye-PCB yesandla. Ifilimu engalungisiwe igezwa nge-lye bese isifunda sefreyimu esidingekayo simbozwa yifilimu ephulukisiwe. Ucwecwe lwethusi olungadingeki lubese luqothulwa ngesisekelo esiqinile, njengeNaOH. Dabula ifilimu ye-photosensitive ephulukisiwe ukuze uveze ucwecwe lwethusi oludingekayo kumjikelezo wesakhiwo se-PCB.

4. Core ipuleti imishini nokuhlolwa

Ipuleti eliyisisekelo lenziwe ngempumelelo. Ngemuva kwalokho yenza umgodi ophambene kupuleti lomgogodla wokuqondanisa okulula nezinye izinto zokusetshenziswa. Lapho ibhodi lomgogodla licindezelwe nezinye izingqimba ze-PCB, alikwazi ukuguqulwa, ngakho-ke kubalulekile ukuhlola. Umshini uzoqhathanisa ngokuzenzakalela nemidwebo yesakhiwo se-PCB ukuhlola amaphutha.

5. Laminated

Lapha sidinga into entsha eluhlaza ebizwa nge-semi-cured sheet, okuyibhodi eliyinhloko nebhodi lomgogodla (ungqimba lwe-PCB & GT; 4), kanye nokunamathisela phakathi kwepuleti eliyisisekelo nocwecwe lwangaphandle lwethusi, kepha futhi kudlala indima ekuvikeleni. Ingqimba engezansi yocwecwe lwethusi nezendlalelo ezimbili zeshidi eliqinile ziye zenziwa kusengaphambili ngomgodi wokuma nendawo yensimbi ephansi indawo elungisiwe, bese ipuleti elihle lomgogodla nalo lifakwa emgodini wokuma, ekugcineni ekugcineni kube nezendlalelo ezimbili lweshidi eliqinile, ungqimba lwefilili yethusi kanye nongqimba lwepuleti le-aluminium embozwe kupuleti lomgogodla. Ibhodi le-PCB liboshwe ngocwecwe lwensimbi lubekwe ekusekelweni, bese lutholakala kumshini wokushisa oshisayo wokuvikela. Ukushisa emshinini oshisayo oshisayo kuncibilikisa i-epoxy resin eshidini elelapheke kancane, ibambe ucwecwe lomgogodla nethusi ndawonye ngaphansi kwengcindezi. Ngemuva kokulaminetha, susa ipuleti lensimbi eliphezulu elicindezela i-PCB. Ngemuva kwalokho ipuleti le-aluminium elinomfutho liyasuswa. Ipuleti le-aluminium nalo lidlala indima ekuhlukaniseni ama-PCBS ahlukile nokuqinisekisa ucwecwe lwethusi olubushelelezi kungqimba olungaphandle lwe-PCB. Zombili izinhlangothi ze-PCB zimbozwe ungqimba lwefilili yethusi ebushelelezi.

6. Ukubhola

Ukuxhuma izingqimba ezine zecwecwe lethusi ezingathintani kwi-PCB, qala ubhoboze izimbobo nge-PCB, bese ufaka izinsimbi zomgodi ukuze uqhube ugesi. Umshini wokubhola we-X-ray usetshenziselwa ukuthola ibhodi elingumongo lesendlalelo sangaphakathi. Umshini uzothola ngokuzenzakalela futhi athole indawo yomgodi ebhodini eliyinhloko, bese wenza izimbobo zokubeka i-PCB ukuqinisekisa ukuthi imishini elandelayo ihamba maphakathi nendawo yomgodi. Beka ishidi le-aluminium emshinini we-punch bese ubeka i-PCB ngaphezulu. Ukwenza ngcono ukusebenza kahle, amabhodi e-PCB afanayo afakwa ndawonye ukuze kwenziwe umgogodla ngokusho kwenani lezendlalelo ze-PCB. Ekugcineni, i-PCB ephezulu imbozwe ungqimba lwe-aluminium, izingqimba ezingaphezulu nezingezansi ze-aluminium ukuze kuthi lapho i-drill ibhola ngaphakathi nangaphandle, ucwecwe lwethusi ku-PCB ngeke ludabuke. Enqubeni yangaphambilini yokuhlanza, i-epoxy encibilikisiwe yadonsiselwa ngaphandle kwe-PCB, ngakho-ke kwakudingeka isuswe. Umshini wokugaya wokufa usika ubungako be-PCB ngokuya ngezixhumanisi ezifanele ze-XY.

7. Izulu lamakhemikhali lethusi odongeni lwepore

Njengoba cishe yonke imiklamo ye-PCB isebenzisa ama-perforations ukuxhuma izingqimba ezihlukile zolayini, ukuxhumana okuhle kudinga ifilimu engu-25 micron yethusi odongeni lomgodi. Lokhu kushuba kwefilimu yethusi kutholakala nge-electroplating, kepha udonga lomgodi lwenziwe nge-non-conductive epoxy resin nebhodi le-fiberglass. Ngakho-ke, isinyathelo sokuqala ukuqoqa ungqimba lwento eqhubayo odongeni lomgodi, bese wenza ifilimu le-1-micron yethusi kuyo yonke indawo ye-PCB, kufaka phakathi udonga lomgodi, ngokufaka amakhemikhali. Yonke inqubo, efana nokwelashwa ngamakhemikhali nokuhlanzwa, ilawulwa yimishini.

8. Dlulisa ukwakheka kwe-PCB yangaphandle

Okulandelayo, ukwakheka kwe-PCB yangaphandle kuzodluliswa kucwecwe lwethusi. Le nqubo ifana naleyo yesakhiwo se-PCB sebhodi elingaphakathi lomgogodla, elidluliswa kucwecwe lwethusi kusetshenziswa ifilimu ekopishelwe nefilimu enesithombe. Umehluko kuphela ukuthi ipuleti elihle lizosetshenziswa njengebhodi. Ukudluliswa kwesakhiwo se-PCB kwangaphakathi kuthatha indlela yokukhupha bese isebenzisa ipuleti elibi njengebhodi. I-PCB embozwe ifilimu eqinisekisiwe ye-photosensitive isekethe, hlanza ifilimu ye-photosensitive engaqinisekisiwe, ifeksi yethusi eveziwe ifakwe, i-PCB layout circuit ivikelwe ifilimu eqinile ye-photosensitive. Isakhiwo se-PCB sangaphandle sidluliswa ngendlela ejwayelekile, futhi ipuleti elihle lisetshenziswa njengebhodi. Indawo embozwe yifilimu ephulukisiwe ku-PCB yindawo engenawo umugqa. Ngemuva kokuhlanza ifilimu engavunyelwe, kwenziwa i-electroplating. Ayikho ifilimu engaqokelwa ugesi, futhi ayikho ifilimu, okokuqala ithusi bese kuba ngothayela. Ngemuva kokukhishwa kwefilimu, kwenziwa ukugcwala kwe-alkaline, futhi ekugcineni kususwe ithini. Iphethini yesifunda isele ebhodini ngoba ivikelwe ngothayela. Bamba i-PCB ne-electroplate ithusi. Njengoba kushiwo ngaphambili, ukuze kuqinisekiswe ukuthi umgodi unokuhamba kahle kukagesi, ifilimu yethusi efakwe odongeni lomgodi kufanele ibe nobukhulu bama-microns angama-25, ngakho-ke uhlelo lonke luzolawulwa ngokuzenzakalela yikhompyutha ukuqinisekisa ukunemba kwalo.

9. I-PCB yangaphandle

Okulandelayo, umugqa ophelele wemishini uqedela inqubo yokuqopha. Okokuqala, hlanza ifilimu ephulukisiwe ebhodini le-PCB. I-alkali eqinile bese isetshenziselwa ukuhlanza ucwecwe lwethusi olungafuneki olumbozwe yilo. Ngemuva kwalokho ukumbozwa kukathayela kucwecwe lwethusi lwesakhiwo se-PCB kuyasuswa ngesisombululo se-tin stripping. Ngemuva kokuhlanza, ukwakheka okungu-4 kwe-PCB kuqediwe.