2 Cov txiaj ntsig ntawm kev sim thiab kev sib tham
2.1Txheej Epitaxialtuab thiab sib xws
Epitaxial txheej tuab, doping concentration thiab uniformity yog ib qho ntawm cov cim qhia tseem ceeb rau kev txiav txim siab qhov zoo ntawm epitaxial wafers. Kev tswj tau qhov tuab, doping concentration thiab uniformity hauv wafer yog qhov tseem ceeb rau kev ua kom muaj kev ua tau zoo thiab kev sib xws ntawmCov khoom siv hluav taws xob SiC, thiab epitaxial txheej thickness thiab doping concentration uniformity kuj yog cov hauv paus tseem ceeb rau kev ntsuas cov txheej txheem muaj peev xwm ntawm cov khoom siv epitaxial.
Daim Duab 3 qhia txog qhov tuab sib xws thiab qhov nkhaus faib tawm ntawm 150 hli thiab 200 hliSiC epitaxial wafers. Nws tuaj yeem pom los ntawm daim duab tias cov kab faib tawm ntawm cov txheej txheem epitaxial thickness yog symmetrical txog qhov chaw nruab nrab ntawm lub wafer. Lub sijhawm txheej txheem epitaxial yog 600s, qhov nruab nrab epitaxial txheej tuab ntawm 150mm epitaxial wafer yog 10.89 um, thiab qhov tuab sib xws yog 1.05%. Los ntawm kev xam, qhov kev loj hlob ntawm epitaxial yog 65.3 um / h, uas yog qib txheej txheem ceev ceev epitaxial. Hauv qab tib lub sijhawm txheej txheem epitaxial, qhov tuab txheej epitaxial ntawm 200 hli epitaxial wafer yog 10.10 um, qhov tuab sib xws yog nyob rau hauv 1.36%, thiab qhov kev loj hlob tag nrho yog 60.60 um / h, uas yog me ntsis qis dua qhov kev loj hlob ntawm 150 hli epitaxial. Qhov no yog vim muaj qhov poob pom tseeb thaum lub silicon qhov chaw thiab cov pa roj carbon qhov chaw ntws los ntawm sab saud ntawm lub chamber tshuaj tiv thaiv los ntawm qhov chaw wafer mus rau sab hauv qab ntawm lub chamber tshuaj tiv thaiv, thiab thaj tsam 200 hli wafer loj dua 150 hli. Cov roj ntws los ntawm qhov chaw ntawm 200 hli wafer rau qhov deb ntev dua, thiab cov roj siv raws txoj kev ntau dua. Nyob rau hauv qhov xwm txheej uas wafer khaws cia tig, qhov tuab tag nrho ntawm cov txheej epitaxial yog nyias dua, yog li qhov kev loj hlob qeeb dua. Zuag qhia tag nrho, qhov tuab sib xws ntawm 150 hli thiab 200 hli epitaxial wafers zoo heev, thiab lub peev xwm ua haujlwm ntawm cov khoom siv tuaj yeem ua tau raws li qhov xav tau ntawm cov khoom siv zoo.
2.2 Epitaxial txheej doping concentration thiab uniformity
Daim Duab 4 qhia txog qhov sib npaug ntawm cov tshuaj doping concentration thiab kev faib tawm ntawm 150 mm thiab 200 mmSiC epitaxial wafersRaws li pom los ntawm daim duab, qhov nkhaus faib cov concentration ntawm epitaxial wafer muaj qhov sib npaug zoo sib xws piv rau qhov chaw nruab nrab ntawm wafer. Qhov sib npaug ntawm cov doping concentration ntawm 150 mm thiab 200 mm epitaxial txheej yog 2.80% thiab 2.66% feem, uas tuaj yeem tswj tau hauv 3%, uas yog qib zoo heev rau cov khoom siv thoob ntiaj teb zoo sib xws. Qhov nkhaus doping concentration ntawm epitaxial txheej yog faib rau hauv "W" duab raws li txoj kab uas hla, uas feem ntau yog txiav txim siab los ntawm thaj chaw ntws ntawm lub cub tawg kub phab ntsa epitaxial, vim tias qhov kev taw qhia ntawm cov cua ntawm cov cua ntawm cov cua ntawm cov cua ntawm cov cua ntawm cov cua yog los ntawm qhov kawg ntawm cov cua nkag (upstream) thiab ntws tawm ntawm qhov kawg ntawm cov dej ntws hauv ib txoj kev laminar los ntawm qhov chaw wafer; vim tias qhov "kev poob qis raws txoj kev" ntawm cov pa roj carbon (C2H4) siab dua li ntawm cov silicon (TCS), thaum lub wafer tig, qhov tseeb C/Si ntawm qhov chaw wafer maj mam txo qis ntawm ntug mus rau qhov chaw (qhov chaw carbon hauv qhov chaw tsawg dua), raws li "kev sib tw txoj haujlwm txoj kev xav" ntawm C thiab N, qhov kev sib xyaw doping hauv qhov chaw ntawm lub wafer maj mam txo qis mus rau ntug, txhawm rau kom tau txais kev sib xyaw zoo heev, ntug N2 ntxiv rau kev them nyiaj thaum lub sijhawm epitaxial kom qeeb qeeb qhov kev txo qis ntawm doping concentration los ntawm qhov chaw mus rau ntug, yog li qhov kawg doping concentration nkhaus nthuav tawm "W" duab.
2.3 Cov teeb meem ntawm txheej Epitaxial
Ntxiv rau qhov tuab thiab doping concentration, qib ntawm epitaxial txheej defect tswj kuj yog ib qho tseem ceeb parameter rau kev ntsuas qhov zoo ntawm epitaxial wafers thiab ib qho tseem ceeb qhia txog lub peev xwm ua haujlwm ntawm cov khoom siv epitaxial. Txawm hais tias SBD thiab MOSFET muaj cov kev cai sib txawv rau cov defects, qhov pom tseeb dua ntawm qhov chaw morphology defects xws li poob defects, triangle defects, carrot defects, comet defects, thiab lwm yam yog txhais tias yog killer defects ntawm SBD thiab MOSFET cov khoom siv. Qhov tshwm sim ntawm kev ua tsis tiav ntawm cov chips uas muaj cov defects no yog siab, yog li kev tswj tus lej ntawm cov defects killer yog qhov tseem ceeb heev rau kev txhim kho cov chip yield thiab txo cov nqi. Daim duab 5 qhia txog kev faib tawm ntawm killer defects ntawm 150 mm thiab 200 mm SiC epitaxial wafers. Nyob rau hauv qhov xwm txheej uas tsis muaj qhov tsis sib npaug hauv C / Si piv, carrot defects thiab comet defects tuaj yeem raug tshem tawm, thaum poob defects thiab triangle defects yog cuam tshuam nrog kev tswj hwm kev huv thaum lub sijhawm ua haujlwm ntawm cov khoom siv epitaxial, qib impurity ntawm graphite qhov chaw hauv chav tshuaj tiv thaiv, thiab qhov zoo ntawm lub substrate. Los ntawm Rooj 2, nws tuaj yeem pom tias qhov ceev ntawm 150 hli thiab 200 hli epitaxial wafers tuaj yeem tswj tau hauv 0.3 particles / cm2, uas yog qib zoo heev rau tib hom khoom siv. Qib tswj qhov ceev ntawm 150 hli epitaxial wafer zoo dua li ntawm 200 hli epitaxial wafer. Qhov no yog vim tias cov txheej txheem npaj substrate ntawm 150 hli yog laus dua li ntawm 200 hli, qhov zoo ntawm substrate zoo dua, thiab qib tswj kev tsis huv ntawm 150 hli graphite reaction chamber zoo dua.
2.4 Qhov roughness ntawm Epitaxial wafer
Daim Duab 6 qhia cov duab AFM ntawm qhov chaw ntawm 150 hli thiab 200 hli SiC epitaxial wafers. Nws tuaj yeem pom los ntawm daim duab tias qhov nruab nrab ntawm qhov chaw nruab nrab ntawm qhov sib npaug ntawm Ra ntawm 150 hli thiab 200 hli epitaxial wafers yog 0.129 nm thiab 0.113 nm feem, thiab qhov chaw ntawm cov txheej epitaxial yog du yam tsis muaj qhov pom tseeb ntawm cov kauj ruam macro-step aggregation. Qhov tshwm sim no qhia tau hais tias kev loj hlob ntawm cov txheej epitaxial ib txwm tswj hwm cov kauj ruam ntws loj hlob thaum lub sijhawm tag nrho cov txheej txheem epitaxial, thiab tsis muaj cov kauj ruam aggregation tshwm sim. Nws tuaj yeem pom tias los ntawm kev siv cov txheej txheem kev loj hlob epitaxial zoo tshaj plaws, cov txheej epitaxial du tuaj yeem tau txais ntawm 150 hli thiab 200 hli qis-lub kaum sab xis substrates.
3 Xaus Lus
Cov 150 hli thiab 200 hli 4H-SiC homogeneous epitaxial wafers tau ua tiav rau ntawm cov khoom siv hauv tsev siv cov khoom siv loj hlob 200 hli SiC epitaxial uas tau tsim los ntawm tus kheej, thiab cov txheej txheem homogeneous epitaxial uas haum rau 150 hli thiab 200 hli tau tsim. Tus nqi loj hlob epitaxial tuaj yeem ntau dua 60 μm / h. Thaum ua tau raws li qhov yuav tsum tau ua epitaxy ceev ceev, qhov zoo ntawm epitaxial wafer zoo heev. Qhov sib npaug ntawm cov tuab ntawm 150 hli thiab 200 hli SiC epitaxial wafers tuaj yeem tswj tau hauv 1.5%, qhov sib npaug ntawm cov concentration tsawg dua 3%, qhov ceev ntawm qhov tsis zoo yog tsawg dua 0.3 particles / cm2, thiab qhov roughness ntawm epitaxial nto hauv paus Ra nruab nrab yog tsawg dua 0.15 nm. Cov cim qhia txog cov txheej txheem tseem ceeb ntawm cov epitaxial wafers yog nyob rau theem siab heev hauv kev lag luam.
Tau los ntawm: Cov Khoom Siv Tshwj Xeeb Hauv Kev Lag Luam Hluav Taws Xob
Sau: Xie Tianle, Li Ping, Yang Yu, Gong Xiaoliang, Ba Sai, Chen Guoqin, Wan Shengqiang
(48th Research Institute ntawm Tuam Tshoj Electronics Technology Group Corporation, Changsha, Hunan 410111)
Lub sijhawm tshaj tawm: Cuaj hlis-04-2024