1. The PBGA na-agbakọta naigwe SMT, na a naghị eme usoro nkwụsịtụ tupu ịgbado ọkụ, na-ebute mmebi nke PBGA n'oge ịgbado ọkụ.
Ụdị nkwakọ ngwaahịa SMD: nkwakọ ngwaahịa anaghị ekpuchi ikuku, gụnyere nkwakọ ngwaahịa ite plastik na epoxy resin, nkwakọ ngwaahịa silicone (nke ekpughere na ikuku ikuku, ihe ndị na-emebi mmiri).Ngwunye rọba niile na-amịkọrọ mmiri ma anaghị emechi ya kpamkpam.
Mgbe MSD mgbe ekpughere ya na elureflow ovenokpomọkụ gburugburu ebe obibi, n'ihi infiltration nke MSD esịtidem mmiri na evaporation na-emepụta zuru oke, na-eme ka nkwakọ ngwaahịa plastic igbe si mgbawa ma ọ bụ pin on layered na-eduga jikọọ ibe emebi na esịtidem mgbawa, na oké ikpe, mgbape gbatịa n'elu MSD. , ọbụna na-eme ka MSD balloon na gbawa, mara dị ka "popcorn" phenomenon.
Mgbe ekpughere ikuku ruo ogologo oge, mmiri dị n'ikuku na-agbasa n'ime ihe nkwakọ ngwaahịa na-emepe emepe.
Ná mmalite nke reflow soldering, mgbe okpomọkụ dị elu karịa 100 ℃, elu iru mmiri nke components na-abawanye nwayọọ nwayọọ, na mmiri nke nta nke nta na-anakọta na bonding akụkụ.
N'oge usoro ịgbado ọkụ n'elu ugwu, a na-ekpughe SMD na okpomọkụ karịrị 200 ℃.N'oge mmụba dị elu nke okpomọkụ, ngwakọta nke ihe dị ka mgbasawanye mmiri ngwa ngwa n'ime ihe ndị dị na ya, ihe na-adabaghị n'ihe, na mmebi nke oghere ihe nwere ike iduga n'ịgbawa ngwugwu ma ọ bụ delamination na isi ihe dị n'ime.
2. Mgbe ịgbado ọkụ ụzọ-free mmiri ndị dị otú ahụ dị ka PBGA, onu nke MSD "popcorn" na mmepụta ga-aghọ ihe ugboro ugboro na oké njọ n'ihi na-abawanye nke ịgbado ọkụ okpomọkụ, na ọbụna na-eduga na mmepụta nwere ike ịbụ nkịtị.
Oge nzipu: Ọgọst-12-2021