Industrial PCB electronics PCB eliphezulu TG170 12 umaleko ENIG

I-PCB ye-High Layer (High Layer PCB) yi-PCB (iBhodi yeSekethe eShicileleyo, ibhodi yesekethe eprintiweyo) enemigangatho engaphezu kwe-8. Ngenxa yeenzuzo zayo zebhodi yesekethe ye-multi-layer, uxinano lwesekethe ephezulu inokufezekiswa kwindawo encinci, ivumela uyilo lwesekethe entsonkothileyo, ngoko ifaneleke kakhulu kwi-high-speed digital signal processing, i-microwave radio frequency, imodem, i-high-end server , ukugcinwa kwedatha kunye neminye imimandla. Iibhodi zeesekethe eziphakamileyo ziqhelekileyo zenziwe ngeebhodi eziphezulu ze-TG FR4 okanye ezinye izinto ze-substrate eziphezulu, ezinokuthi zigcine ukuzinza kweesekethe kwiqondo lokushisa eliphezulu, elinomswakama ophezulu, kunye neendawo eziphezulu.

Ngokumalunga namaxabiso e-TG ezixhobo zeFR4

I-FR-4 substrate yinkqubo ye-epoxy resin, ngoko ke ixesha elide, ixabiso le-Tg lelona salathisi liqhelekileyo lisetyenziselwa ukuhlelwa kwe-FR-4 i-substrate grade, ikwayenye yezona zibonakaliso zokusebenza ezibalulekileyo kwinkcazo ye-IPC-4101, ixabiso le-Tg lenkqubo ye-resin, libhekiselele kwizinto ezivela kwi-resin eqinile okanye "iglasi" yesimo esithambileyo okanye iqondo lokushisa elithambileyo. Olu tshintsho lwe-thermodynamic luhlala lubuyiselwa umva nje ukuba i-resin ayiboli. Oku kuthetha ukuba xa into ifudumala ukusuka kwiqondo lokushisa ukuya kwiqondo lokushisa ngaphezu kwexabiso le-Tg, kwaye emva koko ipholile ngaphantsi kwexabiso le-Tg, inokubuyela kwimeko yangaphambili eqinile kunye neempawu ezifanayo.

Nangona kunjalo, xa izinto zifudunyezwa kwiqondo lobushushu elingaphezulu kakhulu kunexabiso layo le-Tg, utshintsho lwemo yesigaba esingenakuguqulwa lunokubangelwa. Umphumo wolu bushushu unento eninzi yokwenza kunye nohlobo lwezinto eziphathekayo, kunye nokuchithwa kwe-thermal ye-resin. Ngokuqhelekileyo, i-Tg ephezulu ye-substrate, iphezulu ukuthembeka kwezinto eziphathekayo. Ukuba i-lead-free welding process yamkelwa, ukushisa kwe-thermal decomposition (Td) ye-substrate kufuneka kuqwalaselwe. Ezinye izalathisi zokusebenza ezibalulekileyo ziquka i-thermal expansion coefficient (CTE), ukufunxwa kwamanzi, iipropathi zokuncamathela zezinto, kunye novavanyo lwexesha lokubeka ngokwesiqhelo olusetyenziswayo olufana novavanyo lwe-T260 kunye ne-T288.

Umahluko ocacileyo phakathi kwezinto ze-FR-4 lixabiso leTg. Ngokutsho kobushushu be-Tg, i-FR-4 PCB yahlulwe ngokubanzi kwi-Tg ephantsi, i-Tg ephakathi kunye neepleyiti ze-Tg eziphezulu. Kushishino, i-FR-4 ene-Tg ejikeleze i-135℃ idla ngokuhlelwa njenge-Tg PCB ephantsi; I-FR-4 malunga ne-150 ℃ yaguqulelwa kwi-Tg PCB ephakathi. I-FR-4 ene-Tg ejikeleze i-170 ℃ yahlelwa njenge-Tg ephezulu ye-PCB. Ukuba kukho amaxesha amaninzi okucinezela, okanye i-PCB layers (ngaphezu kwe-14 layers), okanye ubushushu obuphezulu be-welding (≥230℃), okanye ubushushu obuphezulu bokusebenza (ngaphezu kwe-100℃), okanye uxinzelelo lwe-thermal welding ephezulu (njenge-soldering wave), i-Tg ephezulu ye-PCB kufuneka ikhethwe.