Ichi chinyorwa chinonyanya kuongorora maitiro maviri anonyanya kushandiswa mu PCB pamusoro pekurapa maitiro: kemikari nickel goridhe uye OSP maitiro matanho uye maitiro.

1. Kemikari nickel goridhe

1.1 Matanho ekutanga

Degreasing → kugeza mvura → neutralization → kugeza mvura → micro-etching → kugeza mvura → pre-soak → palladium activation → kufuridza nekubvongodza mvura kugeza → electroless nickel → kugeza mvura inopisa → electroless goridhe → kudzokorodza kugeza mvura → kugeza mvura mushure mekurapa → kuomesa

1.2 Electroless nickel

A. Kazhinji, electroless nickel yakakamurwa kuva “displacement” uye “self-catalyzed” marudzi. Kune akawanda mafomula, asi zvisinei kuti ndeipi, iwo epamusoro-tembiricha yekuputira mhando iri nani.

B. Nickel Chloride (Nickel Chloride) inowanzoshandiswa semunyu we nickel

C. Inowanzo shandiswa kuderedza mishonga iHypophosphite/Formaldehyde/Hydrazine/Borohydride/Amine Borane

D. Citrate ndiyo inonyanya kuzivikanwa chelating agent.

E. Iyo pH yemushonga wekugezesa inoda kugadziriswa uye kudzorwa. Pachinyakare, ammonia (Amonia) inoshandiswa, asi kunewo maitiro anoshandisa triethanol ammonia (Triethanol Amine). Pamusoro peiyo inogadziriswa pH uye kugadzikana kweammonia pakupisa kwakanyanya, inosanganiswawo ne sodium citrate kuumba yakazara nickel simbi. Chelating agent, kuitira kuti nickel inogona kuiswa pazvikamu zvakaputirwa zvakanaka uye zvinobudirira.

F. Mukuwedzera pakuderedza matambudziko ekusvibiswa, kushandiswa kwe sodium hypophosphite kunewo simba guru pahutano hwekuputira.

G. Iyi ndeimwe yemafomula emakemikari nickel tanks.

Kugadzira maitiro ekuongorora:

A. PH kukosha kunofurira: turbidity ichaitika kana pH iri pasi pe8, uye kuora kuchaitika kana pH yakakwira kupfuura 10. Haina mhedzisiro iri pachena pane phosphorus content, deposition rate uye phosphorus content.

B. Kufurira kwetembiricha: tembiricha ine simba guru pakunaya kwemvura, mvura inonaya zvishoma nezvishoma iri pasi pe70°C, uye mwero inokurumidza kupfuura 95°C uye haigoni kudzorwa. 90°C ndiyo yakanakisisa.

C. Muchikamu chekugadzirisa, sodium citrate content yakakwirira, chelating agent concentration inowedzera, deposition rate inoderera, uye phosphorus content inowedzera ne chelating agent concentration. Iyo phosphorus yemukati ye triethanolamine system inogona kutokwira se15.5%.

D. Sezvo kusungirirwa kweiyo inoderedza sodium dihydrogen hypophosphite inowedzera, chiyero chekuisa chinowedzera, asi chigadziro chekugezera chinoparara kana chinopfuura 0.37M, saka kusungirirwa hakufaniri kunge kwakanyanyisa, kwakanyanya kunokuvadza. Iko hakuna hukama hwakajeka pakati peiyo phosphorus yemukati uye inoderedza mumiriri, saka kazhinji zvakakodzera kudzora kusungirirwa panenge 0.1M.

E. The concentration of triethanolamine kuchakanganisa phosphorus zviri mukati coating uye deposition rate. Iyo yakanyanya kukwirisa, inodzikira iyo phosphorus yemukati uye inononoka deposition, saka zviri nani kuchengeta iyo concentration iri pa 0.15M. Mukuwedzera pakugadzirisa pH, inogonawo kushandiswa sesimbi chelator.

F. Kubva muhurukuro, inozivikanwa kuti sodium citrate concentration inogona kugadziriswa zvinobudirira kuti ibudirire kuchinja phosphorus content yejasi.

H. General kuderedza vamiririri vakakamurwa kuva mapoka maviri:

Nzvimbo yemhangura inowanzova isina-activated surface kuitira kuti iite kuti ibudise magetsi asina kunaka kuti iwane chinangwa che “open plating”. Nzvimbo yemhangura inotora yekutanga electroless palladium nzira. Nokudaro, pane phosphorus eutectosis mukuita, uye 4-12% phosphorus content inowanikwa. Nokudaro, kana uwandu hwe nickel hwakakura, kuvhara kunorasikirwa nekusimba kwayo uye magnetism, uye brittle gloss inowedzera, iyo yakanaka pakudzivirira ngura uye yakaipa kune tambo yekubatanidza uye welding.

1.3 hapana magetsi egoridhe

A. Ndarama isina magetsi yakakamurwa kuita “displacement gold” uye “electroless gold”. Iyo yekutanga ndiyo inonzi “kunyudzwa goridhe” (lmmersion Goridhe plaTIng). Iyo plating layer yakatetepa uye pasi pepamusoro yakazara yakazara uye inomira. Iyo yekupedzisira inogamuchira inodzikisa agent kuti ipe maerekitironi kuitira kuti plating layer irambe yakakora nickel isina electroless.

B. Chimiro chechimiro chemaitiro ekuderedza ndeichi: kuderedza hafu yekuita: Au e-Au0 oxidation half reaction formula: Reda Ox e- full reaction formula: Au Red aAu0 Ox.

C. Pamusoro pekupa goridhe sosi macomplexes uye ekudzikisa maajenti, iyo electroless gold plating formula inofanirawo kushandiswa pamwe chete ne chelating agents, stabilizers, buffers uye kuzvimba ejenti kuti ishande.

D. Mimwe mishumo yekutsvagisa inoratidza kuti kugona uye kunaka kwekemikari yegoridhe kunovandudzwa. Kusarudzwa kwezvinoderedza vamiririri ndiyo kiyi. Kubva pakutanga formaldehyde kusvika ichangoburwa borohydride makomisheni, potassium borohydride ine inowanzoitika. Inonyanya kushanda kana yakashandiswa pamwe chete nemamwe ekuderedza vamiririri.

E. The deposition rate of the coating inowedzera nekuwedzera kwe potassium hydroxide uye kuderedza agent concentration uye yekugeza tembiricha, asi inoderera nekuwedzera kwe potassium cyanide concentration.

F. Kupisa kwekushanda kwemaitiro ekutengeserana kunonyanya kutenderera 90 ° C, inova muedzo mukuru wekugadzikana kwezvinhu.

G. Kana lateral kukura kuitika pamusoro nhete redunhu substrate, zvinogona kukonzera pfupi redunhu ngozi.

H. Goridhe rakatetepa rinowanzoita porosity uye nyore kuumba Galvanic Cell Corrosion K. Dambudziko reporosity yegoridhe rakatetepa rinogona kugadziriswa ne post-processing passivation ine phosphorus.