Lub hauv paus thev naus laus zis rau kev loj hlob ntawmSiC epitaxialcov ntaub ntawv yog thawj zaug siv tshuab tswj qhov tsis zoo, tshwj xeeb tshaj yog rau cov tshuab tswj qhov tsis zoo uas yooj yim ua rau lub cuab yeej tsis ua haujlwm lossis kev ntseeg siab poob qis. Kev kawm txog cov txheej txheem ntawm cov khoom tsis zoo ntawm cov substrate txuas mus rau hauv txheej epitaxial thaum lub sijhawm loj hlob epitaxial, cov kev cai hloov pauv thiab kev hloov pauv ntawm cov tsis zoo ntawm qhov sib txuas ntawm cov substrate thiab txheej epitaxial, thiab cov txheej txheem nucleation ntawm cov tsis zoo yog lub hauv paus rau kev piav qhia txog kev sib raug zoo ntawm cov khoom tsis zoo ntawm cov substrate thiab cov qauv epitaxial, uas tuaj yeem coj kev tshuaj ntsuam substrate thiab kev ua kom zoo dua ntawm cov txheej txheem epitaxial.
Cov kev tsis zoo ntawmsilicon carbide epitaxial txheejfeem ntau muab faib ua ob pawg: cov teeb meem siv lead ua thiab cov teeb meem ntawm qhov chaw. Cov teeb meem siv lead ua, suav nrog cov teeb meem taw tes, cov ntsia hlau tsis sib haum, cov teeb meem microtubule, cov teeb meem ntug tsis sib haum, thiab lwm yam, feem ntau yog los ntawm cov teeb meem ntawm SiC substrates thiab kis mus rau hauv txheej epitaxial. Cov teeb meem ntawm qhov chaw tuaj yeem pom ncaj qha nrog lub qhov muag liab qab siv lub tshuab microscope thiab muaj cov yam ntxwv morphological. Cov teeb meem ntawm qhov chaw feem ntau suav nrog: Kos, Qhov Teeb Meem Triangular, Qhov Teeb Meem Carrot, Kev Poob, thiab Cov Khoom Me, raws li pom hauv Daim Duab 4. Thaum lub sijhawm epitaxial, cov khoom txawv teb chaws, cov teeb meem substrate, kev puas tsuaj ntawm qhov chaw, thiab cov txheej txheem epitaxial yuav cuam tshuam rau hom kev loj hlob ntawm cov kauj ruam hauv zos, ua rau muaj cov teeb meem ntawm qhov chaw.
Rooj 1. Ua rau muaj cov teeb meem matrix thiab cov teeb meem morphology ntawm qhov chaw hauv SiC epitaxial txheej
Cov teeb meem ntawm cov ntsiab lus
Cov teeb meem ntawm cov ntsiab lus yog tsim los ntawm qhov chaw khoob lossis qhov sib txawv ntawm ib qho chaw lattice lossis ntau qhov chaw lattice, thiab lawv tsis muaj qhov ntev. Cov teeb meem ntawm cov ntsiab lus yuav tshwm sim hauv txhua txoj kev tsim khoom, tshwj xeeb tshaj yog hauv kev cog ion. Txawm li cas los xij, lawv nyuaj rau pom, thiab kev sib raug zoo ntawm kev hloov pauv ntawm cov teeb meem ntawm cov ntsiab lus thiab lwm yam teeb meem kuj nyuaj heev.
Cov kav dej me me (MP)
Cov kav dej me me yog cov qhov ntsia hlau uas tsis muaj qhov uas nthuav dav raws txoj kab kev loj hlob, nrog rau Burgers vector <0001>. Lub cheeb ntawm cov raj me me yog txij li ib feem ntawm ib micron mus rau kaum tawm microns. Cov raj me me qhia cov yam ntxwv loj zoo li qhov av ntawm qhov chaw ntawm SiC wafers. Feem ntau, qhov ceev ntawm cov raj me me yog li 0.1 ~ 1cm-2 thiab txuas ntxiv txo qis hauv kev saib xyuas zoo ntawm kev tsim khoom lag luam wafer.
Kev tawg ntawm cov ntsia hlau (TSD) thiab kev tawg ntawm ntug (TED)
Kev tawg ntawm SiC yog qhov tseem ceeb ntawm kev puas tsuaj thiab kev ua tsis tiav ntawm cov khoom siv. Ob qho tib si kev tawg ntawm cov ntsia hlau (TSD) thiab kev tawg ntawm ntug (TED) khiav raws txoj kab loj hlob, nrog rau Burgers vectors ntawm <0001> thiab 1/3 <11–20>, raws li.
Ob qho tib si qhov kev tawg ntawm cov ntsia hlau (TSD) thiab qhov kev tawg ntawm ntug (TED) tuaj yeem txuas ntxiv los ntawm lub substrate mus rau qhov chaw wafer thiab coj cov yam ntxwv me me zoo li qhov chaw (Daim Duab 4b). Feem ntau, qhov ceev ntawm qhov kev tawg ntawm ntug yog li 10 npaug ntawm qhov kev tawg ntawm cov ntsia hlau. Qhov kev tawg ntawm cov ntsia hlau txuas ntxiv, uas yog, txuas ntxiv los ntawm lub substrate mus rau epilayer, kuj tseem yuav hloov mus rau lwm qhov tsis zoo thiab nthuav dav raws txoj kab kev loj hlob. Thaum lub sijhawmSiC epitaxialkev loj hlob, cov ntsia hlau dislocations raug hloov mus ua stacking faults (SF) lossis carrot defects, thaum ntug dislocations hauv epilayers tau pom tias raug hloov los ntawm basal plane dislocations (BPDs) uas tau txais los ntawm lub substrate thaum lub sijhawm epitaxial loj hlob.
Kev puas tsuaj ntawm lub dav hlau yooj yim (BPD)
Nyob rau ntawm SiC basal plane, nrog rau Burgers vector ntawm 1/3 <11–20>. BPDs tsis tshua tshwm sim ntawm qhov chaw ntawm SiC wafers. Lawv feem ntau yog concentrated rau ntawm lub substrate nrog qhov ceev ntawm 1500 cm-2, thaum lawv qhov ceev hauv epilayer tsuas yog li 10 cm-2. Kev kuaj pom ntawm BPDs siv photoluminescence (PL) qhia cov yam ntxwv linear, raws li pom hauv Daim Duab 4c. Thaum lub sijhawmSiC epitaxialkev loj hlob, BPDs txuas ntxiv tuaj yeem hloov pauv mus rau hauv stacking faults (SF) lossis ntug dislocations (TED).
Cov teeb meem ntawm kev sib dhos (SFs)
Cov qhov tsis zoo hauv qhov kev sib dhos ntawm SiC basal plane. Cov qhov tsis zoo ntawm stacking tuaj yeem tshwm sim hauv txheej epitaxial los ntawm kev txais SFs hauv lub substrate, lossis muaj feem cuam tshuam nrog kev nthuav dav thiab kev hloov pauv ntawm basal plane dislocations (BPDs) thiab threading screw dislocations (TSDs). Feem ntau, qhov ceev ntawm SFs tsawg dua 1 cm-2, thiab lawv qhia txog lub ntsej muag triangular thaum pom siv PL, raws li pom hauv Daim Duab 4e. Txawm li cas los xij, ntau hom kev ua yuam kev stacking tuaj yeem tsim tau hauv SiC, xws li Shockley hom thiab Frank hom, vim tias txawm tias me me ntawm kev sib dhos zog tsis sib xws ntawm cov dav hlau tuaj yeem ua rau muaj kev tsis sib xws hauv qhov kev sib dhos.
Kev poob qis
Qhov kev puas tsuaj feem ntau yog los ntawm qhov poob ntawm cov khoom me me ntawm phab ntsa sab saud thiab sab ntawm lub chamber tshuaj tiv thaiv thaum lub sijhawm loj hlob, uas tuaj yeem ua kom zoo dua los ntawm kev ua kom zoo dua cov txheej txheem txij nkawm ntawm cov khoom siv graphite hauv lub chamber tshuaj tiv thaiv.
Qhov tsis zoo ntawm daim duab peb ceg
Nws yog ib qho 3C-SiC polytype inclusion uas nthuav mus rau saum npoo ntawm SiC epilayer raws li qhov kev taw qhia ntawm lub dav hlau, raws li pom hauv Daim Duab 4g. Nws yuav raug tsim los ntawm cov khoom poob rau ntawm qhov chaw ntawm SiC epilayer thaum lub sijhawm loj hlob epitaxial. Cov khoom me me tau muab tso rau hauv epilayer thiab cuam tshuam nrog cov txheej txheem loj hlob, ua rau muaj 3C-SiC polytype inclusions, uas qhia cov yam ntxwv ntawm lub voos xwmfab ntse nrog cov khoom me me nyob ntawm cov vertices ntawm thaj chaw voos xwmfab. Ntau txoj kev tshawb fawb kuj tau hais tias keeb kwm ntawm polytype inclusions rau qhov khawb ntawm qhov chaw, micropipes, thiab cov yam ntxwv tsis raug ntawm cov txheej txheem loj hlob.
Qhov tsis zoo ntawm carrots
Qhov tsis zoo ntawm carrot yog qhov teeb meem stacking uas muaj ob qhov kawg nyob ntawm TSD thiab SF basal crystal planes, xaus los ntawm Frank-type dislocation, thiab qhov loj ntawm qhov tsis zoo ntawm carrot muaj feem cuam tshuam nrog prismatic stacking fault. Kev sib xyaw ua ke ntawm cov yam ntxwv no tsim cov qauv ntawm qhov tsis zoo ntawm carrot, uas zoo li lub carrot zoo li nrog qhov ceev tsawg dua 1 cm-2, raws li pom hauv Daim Duab 4f. Cov tsis zoo ntawm carrot yooj yim tsim ntawm cov khawb polishing, TSDs, lossis cov tsis zoo ntawm substrate.
Cov khawb
Cov khawb yog kev puas tsuaj rau ntawm qhov chaw ntawm SiC wafers uas tsim thaum lub sijhawm tsim khoom, raws li pom hauv Daim Duab 4h. Cov khawb ntawm SiC substrate yuav cuam tshuam rau kev loj hlob ntawm epilayer, tsim ib kab ntawm cov kev sib cais siab hauv epilayer, lossis cov khawb yuav dhau los ua lub hauv paus rau kev tsim cov qhov tsis zoo ntawm carrot. Yog li ntawd, nws yog ib qho tseem ceeb kom txhuam SiC wafers kom zoo vim tias cov khawb no tuaj yeem muaj kev cuam tshuam loj rau kev ua haujlwm ntawm lub cuab yeej thaum lawv tshwm sim hauv thaj chaw ua haujlwm ntawm lub cuab yeej.
Lwm yam kev puas tsuaj ntawm qhov chaw morphology
Cov kauj ruam sib sau ua ke yog qhov tsis zoo ntawm qhov chaw uas tsim thaum lub sijhawm SiC epitaxial kev loj hlob, uas tsim cov duab peb ceg lossis cov yam ntxwv trapezoidal ntawm qhov chaw ntawm SiC epilayer. Muaj ntau lwm yam tsis zoo ntawm qhov chaw, xws li qhov chaw, pob thiab cov xim av. Cov kev tsis zoo no feem ntau yog tshwm sim los ntawm cov txheej txheem kev loj hlob tsis zoo thiab kev tshem tawm tsis tiav ntawm kev puas tsuaj polishing, uas cuam tshuam tsis zoo rau kev ua haujlwm ntawm lub cuab yeej.
Lub sijhawm tshaj tawm: Lub Rau Hli-05-2024