Raws li peb paub, nyob rau hauv daim teb semiconductor, ib leeg siv lead ua silicon (Si) yog cov khoom siv dav tshaj plaws thiab loj tshaj plaws-ntim semiconductor cov khoom siv hauv ntiaj teb. Tam sim no, ntau dua 90% ntawm cov khoom siv semiconductor yog tsim los ntawm cov khoom siv silicon. Nrog rau qhov kev thov ntau ntxiv rau cov khoom siv hluav taws xob thiab cov khoom siv hluav taws xob hauv lub zog niaj hnub no, cov kev xav tau nruj dua tau muab tso rau hauv qhov tseem ceeb ntawm cov khoom siv semiconductor xws li bandgap dav, tawg hluav taws xob lub zog, hluav taws xob saturation tus nqi, thiab thermal conductivity. Hauv qhov xwm txheej no, cov ntaub ntawv dav dav bandgap semiconductor sawv cev los ntawmsilicon carbide(SiC) tau tshwm sim raws li qhov ntxim nyiam ntawm kev siv hluav taws xob siab ceev.
Raws li ib tug compound semiconductor,silicon carbideyog tsis tshua muaj nyob rau hauv cov xwm thiab tshwm nyob rau hauv daim ntawv ntawm cov ntxhia moissanite. Tam sim no, yuav luag tag nrho cov silicon carbide muag nyob rau hauv lub ntiaj teb no yog artificially synthesized. Silicon carbide muaj qhov zoo ntawm kev ua haujlwm siab, siab thermal conductivity, thermal stability zoo, thiab qhov tseem ceeb ntawm kev tawg hluav taws xob. Nws yog ib qho khoom siv zoo tshaj plaws rau kev ua cov khoom siv hluav taws xob siab thiab lub zog siab semiconductor.
Yog li, silicon carbide fais fab semiconductor li cas tsim?
Dab tsi yog qhov txawv ntawm cov khoom siv silicon carbide kev tsim khoom thiab cov txheej txheem kev tsim khoom ntawm silicon-based? Pib los ntawm qhov teeb meem no, “Tej yam hais txogSilicon Carbide DeviceManufacturing" yuav qhia cov secrets ib tug los ntawm ib tug.
I
Txheej txheem khiav ntawm silicon carbide ntaus ntawv raug
Cov txheej txheem tsim cov khoom siv silicon carbide feem ntau zoo ib yam li cov khoom siv silicon, feem ntau suav nrog photolithography, tu, doping, etching, zaj duab xis tsim, thinning thiab lwm yam txheej txheem. Ntau lub tuam txhab tsim hluav taws xob tuaj yeem ua tau raws li qhov kev xav tau ntawm cov khoom siv silicon carbide los ntawm kev txhim kho lawv cov kab ntau lawm raws li cov txheej txheem tsim khoom silicon. Txawm li cas los xij, cov khoom tshwj xeeb ntawm cov ntaub ntawv silicon carbide txiav txim siab tias qee cov txheej txheem hauv nws cov cuab yeej tsim khoom yuav tsum tau tso siab rau cov cuab yeej tshwj xeeb rau kev txhim kho tshwj xeeb kom pab tau cov khoom siv silicon carbide kom tiv taus cov hluav taws xob siab thiab siab tam sim no.
II
Taw qhia rau silicon carbide tshwj xeeb txheej txheem modules
Cov txheej txheem tshwj xeeb ntawm silicon carbide feem ntau suav nrog kev txhaj tshuaj doping, rooj vag qauv tsim, morphology etching, metallization, thiab txheej txheem thinning.
(1) Txhaj tshuaj doping: Vim lub siab carbon-silicon bond zog hauv silicon carbide, impurity atoms nyuaj rau diffuse hauv silicon carbide. Thaum npaj cov khoom siv silicon carbide, doping ntawm PN junctions tsuas yog ua tiav los ntawm ion implantation ntawm qhov kub thiab txias.
Doping feem ntau ua nrog impurity ions xws li boron thiab phosphorus, thiab qhov tob doping feem ntau yog 0.1μm ~ 3μm. High-zog ion implantation yuav rhuav tshem cov qauv lattice ntawm cov khoom siv silicon carbide nws tus kheej. High-temperature annealing yuav tsum tau kho lub lattice puas los ntawm ion implantation thiab tswj cov nyhuv ntawm annealing ntawm nto roughness. Cov txheej txheem tseem ceeb yog kub-kub ion implantation thiab high-temperature annealing.
Daim duab 1 Schematic daim duab ntawm ion implantation thiab high-temperature annealing teebmeem
(2) Kev tsim lub rooj vag: Qhov zoo ntawm SiC/SiO2 interface muaj kev cuam tshuam zoo rau txoj kev tsiv teb tsaws chaw thiab lub rooj vag kev ntseeg siab ntawm MOSFET. Nws yog ib qho tsim nyog los tsim cov rooj vag tshwj xeeb oxide thiab cov txheej txheem tom qab oxidation annealing kom them nyiaj rau dangling bonds ntawm SiC / SiO2 interface nrog cov atoms tshwj xeeb (xws li nitrogen atoms) kom ua tau raws li qhov yuav tsum tau ua ntawm kev ua tau zoo ntawm SiC / SiO2 interface thiab siab. kev tsiv teb tsaws ntawm cov khoom siv. Cov txheej txheem tseem ceeb yog rooj vag oxide high-kub oxidation, LPCVD, thiab PECVD.
Daim duab 2 Schematic daim duab ntawm zoo tib yam oxide zaj duab xis deposition thiab high-kub oxidation
(3) Morphology etching: Silicon carbide cov ntaub ntawv yog inert nyob rau hauv tshuaj solvents, thiab meej morphology tswj tsuas yog ua tiav los ntawm qhuav etching txoj kev; Cov ntaub ntawv npog ntsej muag, xaiv daim npog ntsej muag etching, cov roj sib xyaw, kev tswj cov phab ntsa, etching tus nqi, sidewall roughness, thiab lwm yam yuav tsum tau tsim raws li cov yam ntxwv ntawm cov khoom siv silicon carbide. Cov txheej txheem tseem ceeb yog nyias zaj duab xis deposition, photolithography, dielectric zaj duab xis corrosion, thiab qhuav etching txheej txheem.
Daim duab 3 Schematic daim duab ntawm silicon carbide etching txheej txheem
(4) Metallization: Lub hauv paus electrode ntawm lub cuab yeej yuav tsum tau hlau los ua ib tug zoo low-resistance ohmic hu nrog silicon carbide. Qhov no tsis tsuas yog yuav tsum tau tswj cov txheej txheem ntawm cov hlau deposition thiab tswj lub xeev interface ntawm cov hlau-semiconductor kev sib cuag, tab sis kuj yuav tsum tau kub-kub annealing kom txo tau lub Schottky barrier qhov siab thiab ua tiav hlau-silicon carbide ohmic sib cuag. Cov txheej txheem tseem ceeb yog hlau magnetron sputtering, electron beam evaporation, thiab ceev thermal annealing.
Daim duab 4 Schematic daim duab ntawm magnetron sputtering txoj cai thiab metallization nyhuv
(5) Thinning txheej txheem: Silicon carbide cov khoom muaj cov yam ntxwv ntawm siab hardness, siab brittleness thiab tsawg puas toughness. Nws cov txheej txheem sib tsoo yog qhov ua rau cov khoom tawg yooj yim, ua rau muaj kev puas tsuaj rau wafer nto thiab sub-surface. Cov txheej txheem sib tsoo tshiab yuav tsum tau tsim los ua kom tau raws li cov kev xav tau ntawm cov khoom siv silicon carbide. Cov txheej txheem tseem ceeb yog thinning ntawm kev sib tsoo discs, zaj duab xis nplaum thiab tev, thiab lwm yam.
Daim duab 5 Schematic daim duab ntawm wafer sib tsoo/thinning txoj cai
Post lub sij hawm: Oct-22-2024