Kev ntim khoom siv kiv cua tawm ntawm wafer theem (FOWLP) yog ib txoj hauv kev pheej yig hauv kev lag luam semiconductor. Tab sis cov teebmeem tshwm sim ntawm cov txheej txheem no yog kev sib txhuam thiab kev sib tsoo ntawm cov chip. Txawm hais tias muaj kev txhim kho tas mus li ntawm cov thev naus laus zis wafer theem thiab vaj huam sib luag theem kiv cua tawm, cov teeb meem no cuam tshuam nrog kev molding tseem muaj.
Kev ua kom nkhaus yog tshwm sim los ntawm kev ntswj ntawm cov kua dej molding compound (LCM) thaum lub sijhawm kho thiab txias tom qab molding. Qhov laj thawj thib ob rau kev ua kom nkhaus yog qhov tsis sib xws hauv cov coefficient ntawm thermal expansion (CTE) ntawm silicon chip, molding khoom, thiab substrate. Offset yog vim qhov tseeb tias cov khoom siv molding viscous nrog cov ntsiab lus filler siab feem ntau tsuas yog siv tau rau hauv qhov kub thiab siab. Raws li lub chip raug kho rau lub carrier los ntawm kev sib txuas ib ntus, kev nce kub yuav ua rau cov nplaum mos, yog li ua rau nws lub zog nplaum tsis muaj zog thiab txo nws lub peev xwm los kho lub chip. Qhov laj thawj thib ob rau qhov offset yog tias lub siab xav tau rau molding tsim kev ntxhov siab rau txhua lub chip.
Yuav kom nrhiav tau cov kev daws teeb meem rau cov teeb meem no, DELO tau ua ib txoj kev tshawb fawb txog kev ua tau los ntawm kev muab ib lub analog chip yooj yim rau ntawm ib lub carrier. Hais txog kev teeb tsa, lub carrier wafer raug coated nrog ib daim nplaum bonding ib ntus, thiab lub chip raug muab tso rau hauv qab. Tom qab ntawd, lub wafer raug molded siv cov nplaum DELO uas tsis muaj viscosity thiab kho nrog ultraviolet radiation ua ntej tshem lub carrier wafer. Hauv cov ntawv thov zoo li no, cov khoom sib xyaw thermosetting siab viscosity feem ntau yog siv.
DELO kuj tau piv qhov kev sib txawv ntawm cov khoom siv thermosetting molding thiab cov khoom siv UV kho hauv kev sim, thiab cov txiaj ntsig tau qhia tias cov khoom siv molding ib txwm yuav sib txawv thaum lub sijhawm txias tom qab thermosetting. Yog li ntawd, kev siv chav tsev kub ultraviolet curing es tsis txhob siv cua sov curing tuaj yeem txo qhov cuam tshuam ntawm thermal expansion coefficient mismatch ntawm cov tshuaj molding thiab cov cab kuj, yog li txo qhov kev sib txawv ntawm warping kom ntau li ntau tau.
Kev siv cov khoom siv kho ultraviolet kuj tseem tuaj yeem txo qhov kev siv cov khoom sau, yog li txo qhov viscosity thiab Young's modulus. Qhov viscosity ntawm cov qauv nplaum siv hauv kev sim yog 35000 mPa · s, thiab Young's modulus yog 1 GPa. Vim tsis muaj cua sov lossis siab siab rau cov khoom siv molding, qhov sib txawv ntawm cov chip tuaj yeem txo qis kom tsawg kawg nkaus. Ib qho tshuaj molding ib txwm muaj viscosity txog li 800000 mPa · s thiab Young's modulus hauv qhov ntau ntawm ob tus lej.
Zuag qhia tag nrho, kev tshawb fawb tau qhia tias kev siv cov khoom siv UV kho rau thaj chaw loj yog qhov zoo rau kev tsim cov khoom ntim khoom wafer theem, thaum txo qis kev sib txhuam thiab kev sib tsoo ntawm cov khoom kom ntau li ntau tau. Txawm hais tias muaj qhov sib txawv ntawm cov coefficients thermal expansion ntawm cov khoom siv, cov txheej txheem no tseem muaj ntau daim ntawv thov vim tsis muaj qhov sib txawv ntawm qhov kub thiab txias. Tsis tas li ntawd, kev kho UV kuj tseem tuaj yeem txo lub sijhawm kho thiab kev siv zog.
UV es tsis txhob kho kom sov txo qhov warpage thiab pwm hloov pauv hauv cov ntim khoom wafer-level uas kiv cua tawm
Kev sib piv ntawm 12-nti coated wafers siv cov khoom siv kho cua sov, cov khoom siv ntau (A) thiab cov khoom siv kho UV (B)
Lub sijhawm tshaj tawm: Kaum Ib Hlis-05-2024