Nkhaniyi ikuwunika kwambiri njira ziwiri zomwe zimagwiritsidwa ntchito kwambiri mu PCB Njira yochizira pamwamba: golide wa faifi tambala ndi njira za OSP ndi mawonekedwe.

1. Mankhwala nickel golide

1.1 Njira zoyambira

Degreasing → kutsuka madzi → neutralization → kutsuka madzi → kukhetsa pang’ono → kutsuka madzi → kulowetsedwa kale → kutsegula palladium → kuwomba ndi kusonkhezera kutsuka madzi → nickel yopanda magetsi → kuchapa madzi otentha → golide wopanda magetsi → kutsukanso madzi → kusamba pambuyo pa mankhwala → kuyanika

1.2 Nickel wopanda magetsi

A. Nthawi zambiri, faifi yamagetsi yopanda magetsi imagawidwa kukhala mitundu ya “kusamuka” ndi “yodziyendetsa yokha”. Pali njira zambiri, koma ziribe kanthu kuti ndi iti, mawonekedwe ofunda kwambiri ndi abwinoko.

B. Nickel Chloride (Nickel Chloride) nthawi zambiri amagwiritsidwa ntchito ngati mchere wa nickel

C. Zomwe zimagwiritsidwa ntchito kwambiri zochepetsera ndi Hypophosphite/Formaldehyde/Hydrazine/Borohydride/Amine Borane

D. Citrate ndiye chelating chofala kwambiri.

E. pH ya madzi osambira iyenera kusinthidwa ndikuwongolera. Pachikhalidwe, ammonia (Amonia) amagwiritsidwa ntchito, koma palinso ma formula omwe amagwiritsa ntchito triethanol ammonia (Triethanol Amine). Kuphatikiza pa pH yosinthika komanso kukhazikika kwa ammonia pa kutentha kwakukulu, imaphatikizanso ndi sodium citrate kupanga zitsulo zonse za nickel. Chelating wothandizira, kuti faifi tambala akhoza waikamo pa yokutidwa mbali bwino ndi mogwira mtima.

F. Kuwonjezera pa kuchepetsa mavuto a kuipitsa, kugwiritsa ntchito sodium hypophosphite kumakhudzanso kwambiri ubwino wa zokutira.

G. Iyi ndi imodzi mwa njira zopangira matanki a faifi tambala.

Kusanthula mawonekedwe:

A. PH kufunika kwachikoka: turbidity idzachitika pamene pH ili yotsika kuposa 8, ndipo kuwonongeka kudzachitika pamene pH ili pamwamba kuposa 10. Zilibe zotsatira zoonekeratu pa phosphorous, mlingo wa kuika ndi phosphorous.

B. Chikoka cha kutentha: kutentha kumakhudza kwambiri mvula, momwe zimakhalira pang’onopang’ono pansi pa 70 ° C, ndipo mlingowo ndi wothamanga kuposa 95 ° C ndipo sungathe kulamulidwa. 90 ° C ndi yabwino kwambiri.

C. Mu ndende ya sodium citrate ndi yochuluka, ndende ya chelating imawonjezeka, chiwerengero cha kuchepa chimachepetsa, ndipo phosphorous imawonjezeka ndi ndende ya chelating. Phosphorous zili mu triethanolamine dongosolo akhoza ngakhale kufika 15.5%.

D. Pamene ndende ya kuchepetsa wothandizila sodium dihydrogen hypophosphite ukuwonjezeka, ndi mafunsidwe mlingo ukuwonjezeka, koma kusamba njira kuwola pamene upambana 0.37M, kotero ndende sayenera kukhala okwera kwambiri, kwambiri ndi zoipa. Palibe ubale womveka bwino pakati pa zomwe zili ndi phosphorous ndi chochepetsera, kotero ndizoyenera kuwongolera ndende pafupifupi 0.1M.

E. The ndende ya triethanolamine zidzakhudza phosphorous zili ❖ kuyanika ndi mafunsidwe mlingo. Kuchulukirachulukira, kumachepetsa phosphorous komanso kutsika pang’onopang’ono, kotero ndikwabwino kusunga ndendeyi pafupifupi 0.15M. Kuphatikiza pa kusintha pH, itha kugwiritsidwanso ntchito ngati chelator yachitsulo.

F. Kuchokera pazokambirana, zimadziwika kuti sodium citrate ndende imatha kusinthidwa bwino kuti isinthe phosphorous yomwe ili mu zokutira.

H. General Reduction agents amagawidwa m’magulu awiri:

Pamwamba mkuwa nthawi zambiri sanali adamulowetsa kuti apange magetsi zoipa kukwaniritsa cholinga cha “otseguka plating”. Pamwamba mkuwa utenga woyamba electroless palladium njira. Choncho, pali phosphorous eutectosis zimene zimachitika, ndi 4-12% phosphorous zili wamba. Choncho, pamene kuchuluka kwa faifi tambala ndi lalikulu, ❖ kuyanika amataya elasticity ndi maginito, ndi Chimaona gloss kumawonjezera, amene ndi zabwino kupewa dzimbiri ndi zoipa kwa waya kugwirizana ndi kuwotcherera.

1.3 palibe golide wamagetsi

A. Golide wopanda magetsi amagawidwa kukhala “golide wosasunthika” ndi “golide wopanda magetsi”. Choyamba ndi chomwe chimatchedwa “kumiza golide” (lmmersion Gold plating). Chophimbacho ndi choonda ndipo pansi pake ndi yokutidwa kwathunthu ndikuyima. Wotsirizirayo amavomereza chochepetsera kuti apereke ma elekitironi kuti plating wosanjikiza apitilize kukulitsa faifi yamagetsi yopanda magetsi.

B. Mawonekedwe a njira yochepetsera ndi: kuchepetsa theka lakuchita: Au e-Au0 oxidation theka la reaction formula: Reda Ox e- full reaction formula: Au Red aAu0 Ox.

C. Kuwonjezera pa kupereka magwero a golide ndi kuchepetsa zochepetsera, njira yopangira golide yopanda electroless iyeneranso kugwiritsidwa ntchito pamodzi ndi chelating agents, stabilizers, buffers ndi kutupa kuti zikhale zogwira mtima.

D. Malipoti ena a kafukufuku amasonyeza kuti mphamvu ndi khalidwe la mankhwala a golide amawongoleredwa. Kusankhidwa kwa othandizira ochepetsera ndikofunikira. Kuyambira koyambirira kwa formaldehyde kupita kumagulu aposachedwa a borohydride, potaziyamu borohydride imakhala ndi zotsatira zofala kwambiri. Ndiwothandiza kwambiri ngati agwiritsidwa ntchito limodzi ndi othandizira ena ochepetsera.

E. The mafunsidwe mlingo wa ❖ kuyanika kumawonjezeka ndi kuwonjezeka potaziyamu hydroxide ndi kuchepetsa wothandizila ndende ndi kutentha kusamba, koma amachepetsa ndi kuwonjezeka potaziyamu cyanide ndende.

F. Kutentha kwa ntchito zamalonda nthawi zambiri kumakhala pafupifupi 90 ° C, chomwe ndi chiyeso chachikulu cha kukhazikika kwa zinthu.

G. Ngati kukula kofananirako kumachitika pagawo lopyapyala, kungayambitse ngozi yayifupi.

H. Golide wowonda amatha kukhala ndi porosity komanso yosavuta kupanga Galvanic Cell Corrosion K. Vuto la porosity la golide wochepa thupi likhoza kuthetsedwa ndi post-processing passivation yomwe ili ndi phosphorous.