Ua lilo ka ʻoihana mea PCB i ka manawa nui e hoʻomohala i nā mea e hāʻawi ai i ka nalowale hōʻailona haʻahaʻa loa. No nā hoʻolālā kiʻekiʻe a me nā alapine kiʻekiʻe, e kaupalena nā poho i ka mamao o ka hoʻolaha ʻana o ka hōʻailona a hoʻololi i nā hōʻailona, ​​​​a e hana ia i kahi impedance deviation hiki ke ʻike ʻia ma nā ana TDR. Ke hoʻolālā nei mākou i nā papa kaapuni paʻi a hoʻomohala i nā kaʻapuni e hana ana i nā alapine kiʻekiʻe, hiki ke hoʻowalewale ʻia ke koho i ke keleawe ʻoi aku ka maʻalahi i nā hoʻolālā āpau āu i hana ai.

ʻOiai he ʻoiaʻiʻo ka hana ʻana o ke keleawe keleawe i ka hoʻokaʻawale ʻana i ka impedance a me nā poho, pehea ka maʻalahi o kāu pahu keleawe e pono ai? Aia kekahi mau ala maʻalahi hiki iā ʻoe ke hoʻohana e lanakila ai i nā poho me ke koho ʻole ʻana i ke keleawe ultra-smooth no kēlā me kēia hoʻolālā? E nānā mākou i kēia mau wahi ma kēia ʻatikala, a me nā mea āu e ʻimi ai inā hoʻomaka ʻoe e kūʻai i nā lako PCB stackup.

Nā ʻano oPCB Copper Foil

ʻO ka maʻamau ke kamaʻilio mākou e pili ana i ke keleawe ma nā mea PCB, ʻaʻole mākou e kamaʻilio e pili ana i ke ʻano kikoʻī o ke keleawe, ke kamaʻilio wale nei mākou e pili ana i kona ʻano ʻino. Hoʻopuka nā ʻano hana hoʻoheheʻe keleawe ʻokoʻa i nā kiʻiʻoniʻoni me nā ʻano koʻikoʻi ʻokoʻa, hiki ke ʻike maopopo ʻia ma ke kiʻi scanning electron microscope (SEM). Inā ʻoe e hana ana ma nā alapine kiʻekiʻe (maʻamau ʻo 5 GHz WiFi a i luna paha) a i ʻole ma nā wikiwiki kiʻekiʻe, a laila e hoʻolohe i ke ʻano keleawe i kuhikuhi ʻia i kāu ʻikepili waiwai.

Eia kekahi, e hoʻomaopopo pono i ka manaʻo o nā waiwai Dk ma kahi ʻikepili. E nānā i kēia kūkākūkā podcast me John Coonrod mai Rogers e aʻo hou e pili ana i nā kikoʻī Dk. Me kēlā i ka noʻonoʻo, e nānā kākou i kekahi o nā ʻano like ʻole o ka PCB copper foil.

Electrodeposited

Ma kēia kaʻina hana, ua wili ʻia kahi pahu ma o kahi hopena electrolytic, a hoʻohana ʻia kahi hopena electrodeposition e "hoʻoulu" i ka pahu keleawe ma luna o ka pahu. Ke kaʻi ʻana o ka pahu, ua ʻōwili mālie ʻia ke kiʻi keleawe i loaʻa ma luna o kahi ʻōwili, e hāʻawi ana i kahi ʻāpana keleawe mau i hiki ke ʻōwili ʻia ma luna o kahi laminate. ʻO ka ʻaoʻao pahu o ke keleawe e pili pono i ka ʻawaʻawa o ka pahu, ʻoiai ʻo ka ʻaoʻao i ʻike ʻia e ʻoi aku ka ʻino.

Electrodeposited PCB keleawe foil

Electrodeposited copper production.
I mea e hoʻohana ʻia ai i kahi kaʻina hana PCB maʻamau, e hoʻopaʻa mua ʻia ka ʻaoʻao ʻōpala o ke keleawe i kahi dielectric aniani-resin. ʻO ke koena keleawe i hōʻike ʻia (ʻaoʻao pahu) pono e hoʻomaʻamaʻa me ka manaʻo kemika (e laʻa me ka etching plasma) ma mua o ka hiki ke hoʻohana ʻia i ke kaʻina hana lamination ʻaʻahu keleawe. E hōʻoia kēia e hiki ke hoʻopaʻa ʻia i ka papa aʻe ma ka PCB stackup.

Ke keleawe Electrodeposited Ili

ʻAʻole maopopo iaʻu ka huaʻōlelo maikaʻi loa e pili ana i nā ʻano like ʻole o ka ʻili i mālama ʻianā pepa keleawe, pela ke poo maluna. ʻO kēia mau mea keleawe i ʻike maikaʻi ʻia ma ke ʻano o nā foil i hoʻohuli ʻia, ʻoiai aia ʻelua mau ʻano like ʻole (e nānā i lalo).

Hoʻohana ʻia nā ʻōpala i hoʻohuli ʻia i ka lāʻau lapaʻau i hoʻopili ʻia i ka ʻaoʻao paheʻe (ʻaoʻao pahu) o kahi pepa keleawe electrodeposited. ʻO kahi papa lapaʻau he uhi lahilahi wale nō ia e hoʻopololei i ke keleawe, no laila e hoʻopili nui ʻia i kahi mea dielectric. Hana pū kēia mau lāʻau lapaʻau ma ke ʻano he pale oxidation e pale ai i ka corrosion. Ke hoʻohana ʻia kēia keleawe e hana i nā paneli laminate, ua hoʻopaʻa ʻia ka ʻaoʻao i mālama ʻia i ka dielectric, a ʻo ka ʻaoʻao ʻōpala i koe e ʻike ʻia. ʻAʻole pono ka ʻaoʻao i hōʻike ʻia i kahi ʻano ʻino hou ma mua o ke kālai ʻana; ua lawa ka ikaika e hoʻopaʻa i ka papa aʻe ma ka PCB stackup.

ʻEkolu mau ʻano like ʻole o ka foil keleawe i hoʻohuli ʻia:

Kiʻekiʻe wela elongation (HTE) copper foil: He electrodeposited copper foil keia e like me IPC-4562 Grade 3 kiko'ī. Hoʻohana pū ʻia ka maka i hōʻike ʻia me kahi pale oxidation e pale ai i ka corrosion i ka wā mālama.
ʻO ka pahu i hoʻopaʻa ʻia ʻelua: Ma kēia ʻāpana keleawe, hoʻohana ʻia ka lāʻau lapaʻau i nā ʻaoʻao ʻelua o ke kiʻiʻoniʻoni. Kapa ʻia kēia mea i kekahi manawa i ka pahu pahu i hoʻopaʻa ʻia i ka foil.
Ke keleawe pale: ʻAʻole kēia i helu maʻamau ma ke ʻano he keleawe i mālama ʻia ma luna. Hoʻohana ʻia kēia ʻāpana keleawe i ka uhi metala ma luna o ka ʻaoʻao matte o ke keleawe, a laila hoʻokaʻawale ʻia i ka pae i makemake ʻia.
He mea maʻalahi ka hoʻohana ʻana i ka ʻili i loko o kēia mau mea keleawe: ʻōwili ʻia ka foil ma nā ʻauʻau electrolyte hou aʻe e hoʻopili ana i kahi lua keleawe lua, a ukali ʻia e kahi papa hua pale, a ʻo ka hope he papa kiʻi anti-tarnish.

PCB keleawe pepa

Nā kaʻina hana lapaʻau ʻili no nā pahu keleawe. [Kumu: Pytel, Steven G., et al. "Ka noʻonoʻo ʻana o nā lāʻau keleawe a me nā hopena i ka hoʻolaha ʻana o ka hōʻailona." I ka makahiki 2008 58th Electronic Components and Technology Conference, pp. 1144-1149. IEEE, 2008.]
Me kēia mau kaʻina hana, loaʻa iā ʻoe kahi mea hiki ke hoʻohana maʻalahi i ke kaʻina hana papa maʻamau me ka liʻiliʻi o ka hana hou.

Kopa-Annealed Copper

ʻO nā pepa keleawe i hoʻopaʻa ʻia i ʻōwili ʻia e hele i kahi ʻōwili keleawe ma waena o nā huila, kahi e ʻōwili anu i ka ʻāpana keleawe i ka mānoanoa i makemake ʻia. E ʻokoʻa ke ʻano ʻino o ka pepa foil e pili ana i nā ʻāpana ʻōwili (wikiwiki, kaomi, etc.).

Hiki ke maʻalahi loa ka lau o ka hopena, a ʻike ʻia nā striations ma ka ʻili o ka pepa keleawe i ʻōwili ʻia. Hōʻike nā kiʻi ma lalo i ka hoʻohālikelike ʻana ma waena o kahi pahu keleawe electrodeposited a me kahi foil i hoʻopili ʻia.

PCB keleawe foil hoohalike

Hoʻohālikelike o electrodeposited vs. rolled-annealed foils.
Kopa Haahaa
ʻAʻole kēia he ʻano kala keleawe āu e hana ai me kahi kaʻina hana ʻē aʻe. ʻO ke keleawe haʻahaʻa haʻahaʻa he keleawe electrodeposited i mālama ʻia a hoʻololi ʻia me kahi kaʻina hana micro-roughening e hāʻawi i ka haʻahaʻa haʻahaʻa haʻahaʻa me ka roughening lawa no ka hoʻopili ʻana i ka substrate. ʻO nā kaʻina hana no ka hana ʻana i kēia mau pahu keleawe he mea maʻamau. Hoʻokaʻawale pinepine ʻia kēia mau pepa ma ke ʻano he ultra-low profile (ULP), haʻahaʻa loa (VLP), a me ka haʻahaʻa haʻahaʻa (LP, ma kahi o 1 micron average roughness).

Nā ʻatikala pili:

No ke aha i hoʻohana ʻia ai ka Copper Foil i ka PCB Manufacturing?

Hoʻohana ʻia ʻo Copper Foil ma ka Papa Kaapuni Pai