Dab tsi yog qhov uniformity ntawm nyias zaj duab xis deposition?
Nyias zaj duab xis uniformity hais txog qhov sib xws ntawm cov thickness faib ntawm nyias zaj duab xis hla tag nrho wafer. Zoo uniformity txhais tau hais tias lub thickness ntawm nyias zaj duab xis yog ze heev ntawm txhua txoj hauj lwm ntawm lub wafer.
Dab tsi yog hom ntawm nyias zaj duab xis uniformity?
Feem ntau, cov hauv qab no yog suav tias yog:
● Nyob rau hauv-wafer uniformity: Uniformity hauv ib lub wafer.
● Wafer-rau-wafer uniformity: Uniformity ntawm txawv wafers.
● Ntau-rau-ntau yam uniformity: Uniformity ntawm txawv batch ntawm wafers.
Yuav ua li cas yog uniformity xam?
Ua nyob rau hauv-wafer uniformity ua piv txwv, nws tus qauv sib txawv yog suav nrog cov qauv:
Cov qauv no suav cov hauv paus square ntawm qhov nruab nrab ntawm qhov sib txawv ntawm qhov sib txawv ntawm txhua qhov chaw cov ntaub ntawv thiab qhov nruab nrab ntawm cov ntaub ntawv.
σ (tus qauv sib txawv): Sawv cev rau qib ntawm dispersion ntawm cov ntaub ntawv; qhov loj dua tus qauv sib txawv, qhov ntau dua qhov dispersion.
N: Tag nrho cov ntsiab lus ntawm cov ntaub ntawv ntsuas.
koj: Tus nqi thickness ntawm ith data point.
Txhais tau tias: Qhov nruab nrab tus nqi ntawm tag nrho cov ntaub ntawv cov ntsiab lus.
(ti-Mean)^2: Qhov sib txawv squared ntawm txhua cov ntaub ntawv taw qhia thiab qhov nruab nrab.
∑: Summation.
Cov mis yog me ntsis nyuaj rau kev nkag siab, yog li ntawm no yog ib qho piv txwv:
Nco ntsoov tias peb muaj cov txheej txheem ntawm nyias zaj duab xis thickness cov ntsiab lus: 55.1, 54.8, 55.3, 54.9, 55.0, 54.7, 55.2, 54.9, 55.1, 54.8.
●Ua ntej, suav cov ntsiab lus ntawm 10 cov ntsiab lus no: txhais tau tias=54.98.
●Tom qab ntawd, suav cov squared sib txawv ntawm txhua qhov tuab thiab qhov nruab nrab: {{0}}}0144, 0.0324, {{1{{12} }}}.1024, 0.
●Xam cov qhov sib txawv squared thiab nrhiav qhov nruab nrab: (0.0144 + 0.0324 + 0.1024 + 0.0004 + 0.0004 + 0.{{6} } 0484 + 0 0004 + 0 0144 + 0.0324)=0.3996.
●Thaum kawg, xam tus qauv sib txawv: σ=0.193.
