Cov laj thawj tseem ceeb cuam tshuam rau qhov sib xws ntawm radial resistivity ntawm ib qho muaju yog qhov flatness ntawm cov khoom-kua interface thiab cov nyhuv me me thaum lub sij hawm siv lead ua.
Kev cuam tshuam ntawm flatness ntawm cov khoom-kua interface Thaum lub sij hawm siv lead ua kev loj hlob, yog tias cov yaj yog nplawm tusyees, qhov sib npaug ntawm qhov sib npaug yog cov khoom-kua interface (cov impurity concentration hauv cov yaj yog txawv ntawm impurity concentration hauv cov khoom siv lead ua, yog li ntawd. cov resistivity yog txawv, thiab cov kuj yog sib npaug ntawm cov khoom-kua interface). Thaum lub impurity K <1, lub interface convex rau yaj yuav ua rau lub radial resistivity siab nyob rau hauv nruab nrab thiab qis ntawm ntug, thaum lub interface concave rau yaj yog qhov opposite. Lub radial resistivity uniformity ntawm lub tiaj tus-kua interface yog zoo dua. Cov duab ntawm cov khoom-kua interface thaum lub sij hawm siv lead ua rub tawm yog txiav txim siab los ntawm yam xws li thermal teb faib thiab siv lead ua kev loj hlob kev ua haujlwm tsis. Nyob rau hauv lub ncaj-rub ib leeg siv lead ua, cov duab ntawm cov khoom-kua deg yog qhov tshwm sim ntawm kev sib xyaw ua ke ntawm cov yam ntxwv xws li qhov cub hluav taws kub faib thiab siv lead ua cua sov dissipation.
Thaum rub cov muaju, muaj plaub yam tseem ceeb ntawm kev sib pauv cua sov ntawm cov khoom-kua interface:
Latent cua sov ntawm theem hloov tso tawm los ntawm molten silicon solidification
Thaum tshav kub kub conduction ntawm melting
Thaum tshav kub kub conduction upward los ntawm lub crystal
Radiation cua sov tawm sab nraud los ntawm cov siv lead ua
Lub latent cua sov yog sib xws rau tag nrho cov interface, thiab nws qhov loj me tsis hloov thaum qhov kev loj hlob tsis tu ncua. (Kev kub ceev ceev, ceev txias, thiab nce solidification tus nqi)
Thaum lub taub hau ntawm cov siv lead ua loj hlob nyob ze rau ntawm cov dej-txias cov noob siv lead ua tus pas nrig ntawm lub qhov cub siv lead ua ib leeg, qhov kub gradient nyob rau hauv cov siv lead ua yog loj, uas ua rau lub longitudinal tshav kub conduction ntawm cov siv lead ua ntau dua li ntawm cov hluav taws xob hluav taws xob, yog li ntawd, solid-kua interface convex rau yaj.
Thaum cov siv lead ua loj hlob mus rau nruab nrab, qhov ntev ntawm cov hluav taws xob hluav taws xob sib npaug sib npaug ntawm cov hluav taws xob hluav taws xob, yog li qhov cuam tshuam ncaj qha.
Nyob rau ntawm tus Tsov tus tw ntawm cov siv lead ua, lub longitudinal tshav kub conduction yog tsawg tshaj li cov hluav taws xob hluav taws xob tshav kub, ua rau cov khoom-kua interface concave rau yaj.
Txhawm rau kom tau txais ib qho siv lead ua ib leeg nrog cov qauv radial resistivity, cov khoom-kua interface yuav tsum tau ua kom tiav.
Cov txheej txheem siv yog: ① Kho cov siv lead ua kev loj hlob thermal kom txo cov radial kub gradient ntawm thermal teb.
② Kho qhov siv lead ua rub cov haujlwm tsis ua haujlwm. Piv txwv li, rau ib qho kev sib tshuam convex rau yaj, ua kom cov rub ceev kom nce cov crystal solidification tus nqi. Nyob rau lub sijhawm no, vim qhov nce hauv crystallization latent tshav kub tso tawm ntawm lub interface, melt kub nyob ze ntawm lub interface nce, uas ua rau lub melting ntawm ib feem ntawm cov siv lead ua ntawm lub interface, ua rau lub interface tiaj tus. Ntawm qhov tsis sib xws, yog tias qhov kev loj hlob cuam tshuam yog concave mus rau yaj, qhov kev loj hlob tuaj yeem txo qis, thiab cov yaj yuav ua kom muaj zog sib xws, ua rau kev loj hlob cuam tshuam.
③ Kho qhov kev sib hloov ceev ntawm cov siv lead ua los yog crucible. Ua kom cov siv lead ua kev sib hloov ceev yuav ua rau kom cov kua kub kub nce mus rau hauv qab mus rau sab saum toj ntawm cov khoom-kua interface, ua rau lub interface hloov ntawm convex mus rau concave. Cov kev taw qhia ntawm cov kua ntws los ntawm kev sib hloov ntawm lub crucible yog tib yam li ntawm ntuj convection, thiab cov nyhuv yog kiag li opposite rau cov siv lead ua rotation.
④ Kev nce qhov sib piv ntawm lub puab lub cheeb ntawm lub crucible mus rau txoj kab uas hla ntawm cov siv lead ua yuav flatten cov khoom-kua interface, thiab kuj yuav txo tau qhov dislocation ceev thiab cov pa oxygen cov ntsiab lus nyob rau hauv lub siv lead ua. Feem ntau, lub crucible txoj kab uas hla: siv lead ua txoj kab uas hla = 3 ~ 2.5: 1.
Kev cuam tshuam ntawm lub dav hlau me me
Cov khoom siv-kua cuam tshuam ntawm kev loj hlob siv lead ua feem ntau yog nkhaus vim qhov kev txwv ntawm cov yaj isotherm hauv crucible. Yog tias cov siv lead ua tau nqa sai sai thaum lub sij hawm siv lead ua loj hlob, lub dav hlau me me yuav tshwm sim ntawm cov khoom siv-kua sib txuas ntawm (111) germanium thiab silicon ib leeg muaju. Nws yog (111) atomic close-packed dav hlau, feem ntau hu ua lub dav hlau me.
Lub impurity concentration nyob rau hauv lub me me dav hlau cheeb tsam yog txawv heev los ntawm qhov uas tsis yog-me me dav hlau cheeb tsam. Qhov tshwm sim ntawm qhov txawv txav ntawm impurities hauv thaj chaw dav hlau me yog hu ua cov nyhuv me me.
Vim lub dav hlau me me, qhov kev tiv thaiv ntawm thaj chaw dav hlau me me yuav txo qis, thiab nyob rau hauv cov xwm txheej hnyav, impurity yeeb nkab cores yuav tshwm sim. Yuav kom tshem tawm cov radial resistivity inhomogeneity tshwm sim los ntawm lub dav hlau me me, cov khoom-kua interface yuav tsum tau leveled.
Txais tos txhua tus neeg muas zaub los ntawm thoob plaws lub ntiaj teb tuaj xyuas peb rau kev sib tham ntxiv!
https://www.semi-cera.com/
https://www.semi-cera.com/tac-coating-monocrystal-growth-parts/
https://www.semi-cera.com/cvd-coating/
Post lub sij hawm: Lub Xya hli ntuj-24-2024