Cov teeb meem kev lag luam hauv kev ruaj khov-ua tau zoo silicon carbide wafers nrog kev ua haujlwm ruaj khov suav nrog:
1) Txij li cov crystals yuav tsum loj hlob nyob rau hauv qhov kub-kub kaw qhov chaw siab tshaj 2000 ° C, qhov kev tswj qhov kub thiab txias yog siab heev;
2) Txij li thaum silicon carbide muaj ntau tshaj 200 siv lead ua qauv, tab sis tsuas yog ob peb lub qauv ntawm ib leeg-crystal silicon carbide yog cov khoom siv semiconductor, silicon-to-carbon piv, kev loj hlob kub gradient, thiab siv lead ua kev loj hlob yuav tsum tau tswj kom meej thaum lub sij hawm. cov txheej txheem kev loj hlob crystal. Parameters xws li ceev thiab huab cua txaus siab;
3) Nyob rau hauv txoj kev vapor theem kis tau tus mob, txoj kab uas hla expansion technology ntawm silicon carbide siv lead ua kev loj hlob yog heev nyuaj;
4) Lub hardness ntawm silicon carbide yog ze rau ntawm pob zeb diamond, thiab txiav, sib tsoo, thiab polishing cov txheej txheem nyuaj.
SiC epitaxial wafers: feem ntau yog tsim los ntawm chemical vapor deposition (CVD) txoj kev. Raws li ntau hom doping, lawv muab faib ua n-hom thiab p-hom epitaxial wafers. Hauv tsev Hantian Tiancheng thiab Dongguan Tianyu tuaj yeem muab 4-nti / 6-nti SiC epitaxial wafers. Rau SiC epitaxy, nws yog ib qho nyuaj rau kev tswj nyob rau hauv high-voltage teb, thiab qhov zoo ntawm SiC epitaxy muaj kev cuam tshuam ntau dua rau SiC li. Ntxiv mus, cov khoom siv epitaxial yog monopolized los ntawm plaub lub tuam txhab ua lag luam hauv kev lag luam: Axitron, LPE, TEL thiab Nuflare.
Silicon carbide epitaxialwafer yog hais txog silicon carbide wafer nyob rau hauv uas ib leeg siv lead ua zaj duab xis (epitaxial txheej) nrog rau tej yam yuav tsum tau thiab tib yam li lub substrate siv lead ua yog zus nyob rau hauv thawj silicon carbide substrate. Epitaxial kev loj hlob tsuas yog siv CVD (Chemical Vapor Deposition, ) cov cuab yeej lossis MBE (Molecular Beam Epitaxy) cov cuab yeej. Txij li cov khoom siv silicon carbide tau tsim ncaj qha rau hauv cov txheej txheem epitaxial, qhov zoo ntawm cov txheej txheem epitaxial ncaj qha cuam tshuam rau kev ua haujlwm thiab cov txiaj ntsig ntawm lub cuab yeej. Raws li qhov hluav taws xob tiv thaiv kev ua tau zoo ntawm cov cuab yeej txuas ntxiv nce ntxiv, lub thickness ntawm cov txheej txheem epitaxial yuav thicker thiab kev tswj yuav nyuaj dua. Feem ntau, thaum lub voltage nyob ib ncig ntawm 600V, qhov yuav tsum tau epitaxial txheej thickness yog hais txog 6 microns; Thaum qhov hluav taws xob nyob nruab nrab ntawm 1200-1700V, qhov yuav tsum tau epitaxial txheej thickness ncav cuag 10-15 microns. Yog tias qhov hluav taws xob nce mus txog ntau dua 10,000 volts, txheej txheej epitaxial thickness ntau dua 100 microns yuav tsum tau. Raws li lub thickness ntawm cov epitaxial txheej txuas ntxiv mus, nws yuav nyuaj rau tswj thickness thiab resistivity uniformity thiab defect ntom.
SiC cov khoom siv: Thoob ntiaj teb, 600 ~ 1700V SiC SBD thiab MOSFET tau ua haujlwm. Cov khoom lag luam tseem ceeb ua haujlwm ntawm qhov hluav taws xob qis dua 1200V thiab feem ntau siv rau ntim. Nyob rau hauv cov nqe lus ntawm tus nqi, SiC cov khoom nyob rau hauv lub thoob ntiaj teb kev ua lag luam yog tus nqi ntawm ib ncig ntawm 5-6 lub sij hawm siab tshaj lawv cov neeg sib tw Si. Txawm li cas los xij, tus nqi tau txo qis ntawm tus nqi txhua xyoo ntawm 10%. Nrog rau kev nthuav dav ntawm cov khoom siv hluav taws xob thiab cov cuab yeej tsim khoom hauv 2-3 xyoos tom ntej, cov khoom lag luam yuav nce ntxiv, ua rau txo nqi ntxiv. Nws xav tias thaum tus nqi nce mus txog 2-3 npaug ntawm Si cov khoom, qhov zoo coj los ntawm kev txo cov nqi thiab kev ua haujlwm tau zoo yuav maj mam tsav SiC los tuav qhov chaw lag luam ntawm Si li.
Kev ntim khoom yog ua raws li cov khoom siv silicon, thaum cov khoom siv semiconductor thib peb xav tau kev tsim qauv tshiab. Siv cov qauv ntim khoom siv silicon rau cov khoom siv hluav taws xob dav dav tuaj yeem qhia txog cov teeb meem tshiab thiab cov teeb meem cuam tshuam txog zaus, kev tswj xyuas thermal, thiab kev ntseeg siab. SiC cov khoom siv hluav taws xob muaj kev nkag siab ntau dua rau cov kab mob parasitic capacitance thiab inductance. Piv rau Si cov khoom siv, SiC fais fab chips muaj kev hloov ceev ceev, uas tuaj yeem ua rau overshoot, oscillation, nce kev hloov pauv, thiab txawm tias cov khoom siv tsis raug. Tsis tas li ntawd, SiC cov cuab yeej siv hluav taws xob ua haujlwm ntawm qhov kub siab dua, xav tau cov txheej txheem kev tswj xyuas thermal ntau dua.
Ntau cov qauv sib txawv tau tsim nyob rau hauv kev lag luam dav-bandgap semiconductor fais fab ntim. Ib txwm Si-raws li lub zog module ntim tsis haum lawm. Txhawm rau daws cov teeb meem ntawm cov kab mob parasitic siab thiab tsis zoo cua sov dissipation efficiency ntawm cov tsoos Si-raws li lub hwj chim module ntim, SiC fais fab module ntim txais kev sib txuas wireless thiab ob sab cua txias tshuab hauv nws cov qauv, thiab tseem siv cov khoom siv hluav taws xob zoo dua thermal. conductivity, thiab sim integrate decoupling capacitors, kub / tam sim no sensors, thiab tsav circuits mus rau hauv lub module qauv, thiab tsim ib tug ntau yam ntawm txawv module ntim technologies. Ntxiv mus, muaj kev cuam tshuam kev lag luam siab rau SiC cov cuab yeej tsim khoom thiab cov nqi tsim khoom yog siab.
Silicon carbide li yog tsim los ntawm depositing epitaxial txheej ntawm silicon carbide substrate los ntawm CVD. Cov txheej txheem suav nrog kev tu, oxidation, photolithography, etching, stripping ntawm photoresist, ion implantation, tshuaj vapor deposition ntawm silicon nitride, polishing, sputtering, thiab tom qab ua cov kauj ruam los tsim cov qauv ntaus ntawv ntawm SiC ib leeg siv lead ua substrate. Cov khoom tseem ceeb ntawm SiC muaj xws li SiC diodes, SiC transistors, thiab SiC fais fab modules. Vim muaj cov yam ntxwv xws li cov khoom siv hluav taws xob qeeb qeeb thiab cov txiaj ntsig qis, cov khoom siv silicon carbide muaj cov nqi tsim khoom siab.
Tsis tas li ntawd, kev tsim khoom siv silicon carbide muaj qee yam kev nyuaj:
1) Nws yog ib qho tsim nyog los tsim cov txheej txheem tshwj xeeb uas ua raws li cov yam ntxwv ntawm cov khoom siv silicon carbide. Piv txwv li: SiC muaj qhov siab melting point, uas ua rau cov tshuaj thermal diffusion tsis zoo. Nws yog ib qho tsim nyog yuav tsum siv ion implantation doping txoj kev thiab raug tswj tsis tau xws li kub, cua sov tus nqi, ntev, thiab roj ntws; SiC yog inert rau chemical solvents. Cov txheej txheem xws li qhuav etching yuav tsum tau siv, thiab cov ntaub ntawv npog ntsej muag, cov roj sib tov, kev tswj ntawm txoj kab nqes ntawm phab ntsa, etching tus nqi, sidewall roughness, thiab lwm yam yuav tsum tau optimized thiab tsim;
2) Kev tsim cov hlau electrodes ntawm silicon carbide wafers xav tau kev tiv thaiv qis dua 10-5Ω2. Cov khoom siv hluav taws xob uas ua tau raws li qhov yuav tsum tau ua, Ni thiab Al, tsis zoo thermal stability siab tshaj 100 ° C, tab sis Al / Ni muaj thermal stability zoo dua. Kev tiv thaiv tshwj xeeb ntawm / W / Au cov khoom siv electrode yog 10-3Ω2 siab dua;
3) SiC muaj siab txiav hnav, thiab lub hardness ntawm SiC yog thib ob tsuas yog pob zeb diamond, uas tso rau pem hauv ntej cov kev xav tau ntau dua rau kev txiav, sib tsoo, polishing thiab lwm yam thev naus laus zis.
Ntxiv mus, trench silicon carbide fais fab mov yog qhov nyuaj rau kev tsim khoom. Raws li cov qauv sib txawv, silicon carbide fais fab tuaj yeem muab faib ua cov cuab yeej siv thiab cov khoom siv trench. Planar silicon carbide fais fab cov cuab yeej muaj chav tsev zoo sib xws thiab cov txheej txheem tsim khoom yooj yim, tab sis nws muaj feem cuam tshuam rau JFET thiab muaj cov kab mob parasitic siab thiab tiv thaiv hauv xeev. Piv nrog rau cov cuab yeej siv, cov khoom siv hluav taws xob silicon carbide trench muaj qhov sib xws ntawm chav tsev qis thiab muaj cov txheej txheem tsim khoom ntau dua. Txawm li cas los xij, cov qauv trench yog qhov tsim nyog los ua kom cov khoom siv ceev ceev thiab tsis tshua muaj peev xwm tsim cov nyhuv JFET, uas muaj txiaj ntsig zoo los daws qhov teeb meem ntawm kev txav mus los. Nws muaj cov khoom zoo xws li kev tiv thaiv me me, me me parasitic capacitance, thiab kev siv hluav taws xob tsawg. Nws muaj cov nqi tseem ceeb thiab kev ua tau zoo thiab tau dhau los ua cov kev taw qhia tseem ceeb ntawm kev tsim cov khoom siv hluav taws xob silicon carbide. Raws li Rohm lub vev xaib official, ROHM Gen3 qauv (Gen1 Trench qauv) tsuas yog 75% ntawm Gen2 (Plannar2) nti cheeb tsam, thiab ROHM Gen3 tus qauv kev tiv thaiv raug txo los ntawm 50% nyob rau hauv tib lub nti loj.
Silicon carbide substrate, epitaxy, pem hauv ntej-kawg, R & D cov nuj nqis thiab lwm tus account rau 47%, 23%, 19%, 6% thiab 5% ntawm cov nqi tsim khoom ntawm silicon carbide li.
Thaum kawg, peb yuav tsom mus rau kev rhuav tshem cov txheej txheem kev cuam tshuam ntawm substrates hauv silicon carbide kev lag luam saw.
Kev tsim cov txheej txheem ntawm silicon carbide substrates yog zoo ib yam li cov silicon-based substrates, tab sis nyuaj dua.
Kev tsim cov txheej txheem ntawm silicon carbide substrate feem ntau suav nrog cov khoom siv raw synthesis, siv lead ua kev loj hlob, ingot ua, ingot txiav, wafer sib tsoo, polishing, tu thiab lwm yam txuas.
Cov theem ntawm kev loj hlob siv lead ua yog qhov tseem ceeb ntawm tag nrho cov txheej txheem, thiab cov kauj ruam no txiav txim siab cov khoom siv hluav taws xob ntawm silicon carbide substrate.
Silicon carbide cov ntaub ntawv yog qhov nyuaj rau loj hlob nyob rau hauv cov kua theem nyob rau hauv ib txwm tej yam kev mob. Txoj kev loj hlob ntawm vapor theem nrov nyob rau hauv kev ua lag luam niaj hnub no muaj qhov kub thiab txias siab tshaj 2300 ° C thiab yuav tsum tau tswj xyuas qhov kub thiab txias. Tag nrho cov txheej txheem ua haujlwm yog yuav luag tsis yooj yim los soj ntsuam. Ib qho yuam kev me ntsis yuav ua rau cov khoom seem. Hauv kev sib piv, cov khoom siv silicon tsuas yog xav tau 1600 ℃, uas yog qis dua. Kev npaj silicon carbide substrates kuj ntsib teeb meem xws li kev loj hlob siv lead ua qeeb thiab cov ntaub ntawv siv lead ua siab. Silicon carbide wafer kev loj hlob yuav siv li 7 mus rau 10 hnub, thaum silicon pas nrig rub tsuas yog siv 2 thiab ib nrab hnub. Ntxiv mus, silicon carbide yog cov khoom uas nws hardness yog thib ob tsuas yog pob zeb diamond. Nws yuav poob ntau heev thaum txiav, sib tsoo, thiab polishing, thiab qhov tso zis piv tsuas yog 60%.
Peb paub tias qhov sib txawv yog nce qhov loj ntawm silicon carbide substrates, raws li qhov loj ntxiv mus ntxiv, cov kev cai rau txoj kab uas hla expansion tshuab tau nce siab dua. Nws yuav tsum muaj kev sib xyaw ua ke ntawm ntau yam kev tswj xyuas kom ua tiav qhov kev loj hlob ntawm cov muaju.
Post lub sij hawm: May-22-2024