Nzwisisa chii chinonzi ENIG Black Pad uye nzira yekudzivirira?

ENIG (Electroless Nickel Immersion Gold) Black Pad inoreva kukanganisa kwakananga kunoitika mukugadzirwa kwemabhodhi ecircuit akadhindwa (PCBs) anoshandisa ENIG surface finish . Kukanganisa uku kunoratidzwa nekuumbwa kwechitarisiko chedema kana cherima pane nickel layer, iyo inowanzo kuwanikwa pasi pegold layer mumaPCB akapedzwa neENIG. Chiitiko cheblack pad chinonyanya kukanganisa kugona kwekusunganidzwa uye kuvimbika kwemaPCB, sezvo ichikanganisa kuvimbika kwemajoini esolder pakati pePCB nezvikamu.

Chii Chinokonzera ENIG Nhema Pad?

Iyo dema pad nyaya inowanzonzi inokonzerwa nezvinetso mumakemikari process panguva nickel plating nhanho. Zvinokonzera kukanganisa uku zvinosanganisira:

Yakawandisa Phosphorus muNickel Bath

Iyo yakakosha nyaya inowanzo dzokera kumashure kune mamiriro mukati me nickel plating yekugezera, ine yakawandisa phosphorus yemukati iriyo inonyanya kunetseka. Phosphorus inowedzerwa kune nickel kuti iwedzere kusimba kwayo uye kuoma kwayo. Nekudaro, kana iyo phosphorus yemukati ichipfuura iyo yakakwana huwandu (kazhinji 7% -11%), inogona kutungamirira kune brittle uye porous nickel layer inokonzeresa kuita ngura. Munguva yekushambadzira kana kuyerera kwemaitiro, nzvimbo idzi dzinonyanya kutambudzika, uye yakaremara nickel layer inogona kutsemuka zviri nyore, ichifumura iri pasi "black" nickel layer uye ichipa chakaremara zita racho.

Mhedzisiro yeMazhinji Reflow Maitiro

Multiple reflow maitiro anowedzera iyo dema pad mamiriro nekuwedzera kunyungudutsa nickel kubva pamusoro, nekudaro kuwedzera phosphorus-to-nickel ratio kupfuura chikumbaridzo. Imwe neimwe inotevera reflow kutenderera inogona kubvisa yakawedzera nickel, ichisiya yakakwira phosphorus. Izvi zvakagadziriswa zvinoderedza kusimba kwe nickel uye zvinokurudzira kuumbwa kwechiitiko cheblack pad.

Yakanyanya Kunyudza Goridhe Deposition

Chimwe chinokonzera huwandu hwegoridhe rakaiswa panguva yekunyudzwa kwegoridhe. Iyo IPC miyero inokurudzira kukora kwegoridhe kwe2-4 micro-inches kuti ive nechokwadi chekushanda kwakakwana. Nekudaro, kuti isangane nezvinodiwa chaizvo kana kuona hushoma hwe3 micro-inches yegoridhe, vagadziri vanogona kushandura chemistry kuti ikurumidze kuburitsa goridhe mwero. Iyi inokurumidza kuita inogona kutungamirira ku "hyper-corrosion" ye nickel layer. Sezvo maitiro ekuisa goridhe achingozvimisa-kumira kana nickel yese yakafumurwa yavharwa-kumanikidza goridhe rakakora rinogona kukonzera kuonda kwakanyanyisa nickel, zvichiwedzera njodzi yekukanganisa padhi dema.

Mhinduro dzeKuderedza Njodzi Pad Pad

Kuongorora uye Kuzivikanwa

Visual Inspection: Gara uchiongorora pamusoro pemapuranga akapedzwa zviratidzo zvepadhi dema, senge zvivakwa zvakatsemuka kana nzvimbo dzisina kurongwa. Kusavapo kwemaspikes nemabhandi akasviba padyo nemiganhu yenickel kunogona kuratidza kuti pad dema inogona kunge isiri nyaya.
Advanced Inspection Techniques: Shandisa advanced Optical and scanning matekiniki kuti uone zvisingaoneki zviratidzo zveblack pad zvingasaonekwe nemaziso.

Nickel Bath Management

Stoichiometry Kudzora: Nyatsodzora iyo stoichiometry yenickel yekugezesa kuchengetedza yakakwana chiyero chenickel kune goridhe. Iyi chiyero yakakosha mukudzivirira yakawandisa phosphorus yemukati inobatsira kune dema pad.
pH Level Monitoring: Tarisa iyo pH level yenickel yekugezesa zvakanyanya. Iyo pH level inokonzeresa kuti yakawanda sei phosphorous yakapfava uye inogona kuve inotaridza kunaka kweiyo nickel layer.
Nickel Bath Maintenance: Kuchengetedza nguva dzose yekugeza nickel, kusanganisira kubviswa kwezvinosvibisa uye kugadzikana kwekuumbwa kwekugezera, zvakakosha. Kushandisa chelating agents uye stabilizers kunogona kubatsira kudzivirira kuputika kusati kwasvika kubva nickel mubhavhu.

Pre-kurapwa uye Bath Chemistry

Kunyatsochenesa: Itai maitiro akaomarara ekutanga-kurapa kubvisa mafuta, masara, uye zvimwe zvinosvibisa kubva paPCB pamusoro usati waiswa. Iyi nhanho inovimbisa nzvimbo yakachena yekuputira kunoshanda.
Chemistry Optimization: Gadzirisa kemikari yekugezesa nickel, kusanganisira nekuchenjerera kushandiswa kwezvinopenya uye levelers, kusimudzira yunifomu uye isina kuremara nickel layer.

Alternative Finishes

Ongororo yedzimwe nzira: Pamaapplication ane njodzi yeblack pad, funga mamwe mapeji epamusoro asingaratidzi kukanganiswa kwakafanana kune ichi chikanganiso. Sarudzo dzakaita seImmersion Silver, OSP (Organic Solderability Preservatives), uye Lead-Mahara HASL inogona kuve inogoneka dzimwe nzira zvichienderana nezvinodiwa zvekushandisa.

Vendor Verification

Hunhu Simbiso: Ita shuwa kuti chero ENIG mupi webasa ane yakanyatso kudzora maitiro ekugezesa nickel yavo uye inoomerera kune yakaomesesa yemhando zviyero. Kuongororwa kwemaitiro evanopa, kusanganisira maitiro avo ekugadzirisa yekugezera uye PCB pre-kurapa, yakakosha mukuderedza njodzi yeblack pad.

Kuti uwane ongororo yakazara yekugadzira, shandisa chinyorwa chino pamwe chete nekugadzira kweFPC uye kugadzira kwePCB kwakapfava kana uchitarisa zvinodiwa pakugadzira zvinhu, kugadzira, kana kuyedza.