Okwangoku, ishishini leSiC litshintsha ukusuka kwi-150 mm (6 intshi) ukuya kwi-200 mm (8 intshi). Ukuze kuhlangatyezwane nemfuno engxamisekileyo yee-wafers ezinkulu nezikumgangatho ophezulu zeSiC homoepitaxial kushishino, i-150mm kunye ne-200mm.Iiwafers ze-4H-SiC homoepitaxialzilungiswe ngempumelelo kwiindawo zasekhaya kusetyenziswa izixhobo zokukhulisa i-epitaxial ze-200mm SiC ezizimeleyo. Inkqubo ye-homoepitaxial efanelekileyo kwi-150mm kunye ne-200mm yaphuhliswa, apho izinga lokukhula kwe-epitaxial linokuba ngaphezulu kwe-60um/h. Ngelixa ihlangabezana ne-epitaxy ekhawulezayo, umgangatho we-epitaxial wafer ubalasele. Ubukhulu obufanayo be-150 mm kunye ne-200 mmIiwafer ze-SiC epitaxialinokulawulwa ngaphakathi kwe-1.5%, ukufana koxinzelelo kungaphantsi kwe-3%, uxinano lwesiphene esibulalayo lungaphantsi kwe-0.3 particles/cm2, kwaye i-epitaxial surface roughness root mean square Ra ingaphantsi kwe-0.15nm, kwaye zonke izalathisi zenkqubo ephambili zikwinqanaba eliphezulu leshishini.
I-Silicon Carbide (i-SiC)yenye yezona zinto zimela izixhobo ze-semiconductor zesizukulwana sesithathu. Ineempawu zokuba namandla entsimi aphantsi kakhulu, ukuqhuba kakuhle kobushushu, isantya esikhulu sokutyibilika kwe-electron saturation, kunye nokumelana okukhulu kwemisebe. Yandise kakhulu amandla okucubungula amandla ezixhobo zamandla kwaye inokuhlangabezana neemfuno zenkonzo zesizukulwana esilandelayo sezixhobo ze-elektroniki zamandla kwizixhobo ezinamandla aphezulu, ubungakanani obuncinci, ubushushu obuphezulu, imisebe ephezulu kunye nezinye iimeko ezigqithisileyo. Inganciphisa indawo, inciphise ukusetyenziswa kwamandla kwaye inciphise iimfuno zokupholisa. Izise utshintsho olukhulu kwizithuthi zamandla amatsha, ukuthuthwa koololiwe, iigridi ezikrelekrele kunye nezinye iindawo. Ke ngoko, ii-semiconductors ze-silicon carbide ziye zaqatshelwa njengezixhobo ezifanelekileyo eziya kukhokela isizukulwana esilandelayo sezixhobo ze-elektroniki zamandla aphezulu. Kwiminyaka yakutshanje, ngenxa yenkxaso yemigaqo-nkqubo kazwelonke yophuhliso lweshishini le-semiconductor lesizukulwana sesithathu, uphando kunye nophuhliso kunye nokwakhiwa kwenkqubo yeshishini lezixhobo ze-SiC eziyi-150 mm ziye zagqitywa eTshayina, kwaye ukhuseleko lwekhonkco lemizi-mveliso luqinisekisiwe ngokusisiseko. Ke ngoko, ingqwalasela yeshishini iye yatshintsha kancinci kancinci yaya kulawulo lweendleko kunye nokuphuculwa kokusebenza kakuhle. Njengoko kubonisiwe kwiTheyibhile 1, xa kuthelekiswa ne-150 mm, i-200 mm SiC inomlinganiselo ophezulu wokusetyenziswa, kwaye imveliso yeetships ze-single wafer inganyuswa malunga namaxesha ali-1.8. Emva kokuba ubuchwepheshe buvuthiwe, iindleko zokuvelisa itships enye zingancitshiswa ngama-30%. Ukuphumelela kwezobuchwepheshe kwe-200 mm yindlela ethe ngqo "yokunciphisa iindleko kunye nokwandisa ukusebenza kakuhle", kwaye ikwasisitshixo kwishishini le-semiconductor lelizwe lam ukuba "lisebenze ngaxeshanye" okanye "likhokele".
Yahlukile kwinkqubo yesixhobo se-Si,Izixhobo zamandla ze-semiconductor ze-SiCZonke ziyacutshungulwa kwaye zilungiswa ngee-epitaxial layers njengelitye lembombo. Ii-epitaxial wafers zizinto ezisisiseko ezibalulekileyo kwizixhobo zamandla ze-SiC. Umgangatho womaleko we-epitaxial umisela ngokuthe ngqo isivuno sesixhobo, kwaye iindleko zaso zibiza i-20% yeendleko zokuvelisa iitship. Ke ngoko, ukukhula kwe-epitaxial likhonkco eliphakathi elibalulekileyo kwizixhobo zamandla ze-SiC. Umda ophezulu wenqanaba lenkqubo ye-epitaxial umiselwa zizixhobo ze-epitaxial. Okwangoku, inqanaba lokufumana indawo yezixhobo ze-epitaxial ze-150mm SiC eTshayina liphezulu kakhulu, kodwa uyilo lulonke lwe-200mm lusemva kwinqanaba lamazwe ngamazwe ngaxeshanye. Ke ngoko, ukuze kusonjululwe iimfuno ezingxamisekileyo kunye neengxaki zemiqobo yokwenziwa kwezinto ezinkulu, ezikumgangatho ophezulu ze-epitaxial zophuhliso lweshishini le-semiconductor lasekhaya lesizukulwana sesithathu, eli phepha lazisa izixhobo ze-epitaxial ze-200 mm SiC eziphuhliswe ngempumelelo kwilizwe lam, kwaye lifunda inkqubo ye-epitaxial. Ngokwenza ngcono iiparameter zenkqubo ezifana nobushushu benkqubo, izinga lokuhamba kwegesi yomthwali, umlinganiselo we-C/Si, njl.njl., ukufana koxinzelelo <3%, ukunganyaniseki kobukhulu <1.5%, uburhabaxa be-Ra <0.2 nm kunye noxinano olubi lwe-defect <0.3 grains/cm2 ye-150 mm kunye ne-200 mm SiC epitaxial wafers ezine-200 mm silicon carbide epitaxial furnace ephuhliswe ngokuzimeleyo ziyafumaneka. Inqanaba lenkqubo yezixhobo linokwanelisa iimfuno zokulungiswa kwesixhobo samandla se-SiC esikumgangatho ophezulu.
1 Uvavanyo
1.1 Umgaqo weI-SiC epitaxialinkqubo
Inkqubo yokukhula kwe-homoepitaxial ye-4H-SiC ibandakanya ikakhulu amanyathelo amabini aphambili, oko kukuthi, ukugrumba okuphezulu kwi-substrate ye-4H-SiC kunye nenkqubo yokufumba umphunga wekhemikhali efanayo. Injongo ephambili yokugrumba kwi-substrate kukususa umonakalo ongaphantsi komhlaba we-substrate emva kokugrumba kwe-wafer, ulwelo lokugrumba olusele, amasuntswana kunye nomaleko we-oxide, kwaye isakhiwo se-atomic step esiqhelekileyo sinokwenziwa kumphezulu we-substrate ngokugrumba. Ukugrumba ngaphakathi kwi-substrate kudla ngokwenziwa kwi-hydrogen atmosphere. Ngokweemfuno zenkqubo yokwenyani, inani elincinci legesi encedisayo linokongezwa, njenge-hydrogen chloride, i-propane, i-ethylene okanye i-silane. Ubushushu bokugrumba ngaphakathi kwi-hydrogen ngokubanzi bungaphezulu kwe-1 600 ℃, kwaye uxinzelelo lwegumbi lokusabela ngokubanzi lulawulwa ngaphantsi kwe-2×104 Pa ngexesha lenkqubo yokugrumba.
Emva kokuba umphezulu we-substrate usebenze ngokugrumba ngaphakathi, ungena kwinkqubo yokubeka umphunga weekhemikhali obushushu obuphezulu, oko kukuthi, umthombo wokukhula (njenge-ethylene/propane, i-TCS/silane), umthombo we-doping (i-n-type doping source nitrogen, umthombo we-p-type doping TMal), kunye negesi encedisayo efana ne-hydrogen chloride zithuthwa ziye kwigumbi lokusabela ngokuhamba okukhulu kwegesi ethwala (ngesiqhelo i-hydrogen). Emva kokuba igesi isabela kwigumbi lokusabela lobushushu obuphezulu, inxalenye ye-precursor isabela ngokweekhemikhali kwaye ifunxe kumphezulu we-wafer, kwaye umaleko we-epitaxial we-4H-SiC one-homogeneous one-concentration ethile ye-doping, ubukhulu obuthile, kunye nomgangatho ophezulu wenziwa kumphezulu we-substrate kusetyenziswa i-substrate ye-4H-SiC enye njengetemplate. Emva kweminyaka yophando lobuchwephesha, itekhnoloji ye-4H-SiC homoepitaxial sele ivuthiwe kwaye isetyenziswa kakhulu kwimveliso yemizi-mveliso. Itekhnoloji ye-4H-SiC homoepitaxial esetyenziswa kakhulu kwihlabathi ineempawu ezimbini eziqhelekileyo:
(1) Ukusebenzisa i-off-axis (xa ithelekiswa ne-<0001> crystal plane, ukuya kwicala le-crystal le-<11-20>) i-oblique cut substrate njengetemplate, umaleko we-epitaxial one-crystal 4H-SiC epitaxial ongenazo izinto ezingcolileyo ufakwa kwi-substrate ngendlela ye-step-flow growth mode. Ukukhula kwe-homoepitaxial kwe-4H-SiC kwasekuqaleni kusetyenziswe i-positive crystal substrate, oko kukuthi, i-<0001> Si plane yokukhula. Uxinano lwamanyathelo e-atomic kumphezulu we-positive crystal substrate luphantsi kwaye ama-terraces abanzi. Ukukhula kwe-nucleation okunemilinganiselo emibini kulula ukwenzeka ngexesha lenkqubo ye-epitaxy yokwenza i-3C crystal SiC (3C-SiC). Ngokusika i-off-axis, amanyathelo e-atomic anoxinano oluphezulu, oluncinci lwe-terrace ububanzi anokungeniswa kumphezulu we-4H-SiC <0001> substrate, kwaye i-adsorbed precursor inokufikelela ngempumelelo kwindawo ye-atomic step position ngamandla aphantsi omphezulu ngokusasazeka komphezulu. Kwinyathelo, indawo yokubophelelana kwe-atom/i-molecular group ikhethekile, ngoko ke kwimo yokukhula kokuhamba kwenyathelo, umaleko we-epitaxial unokuphila ngokugqibeleleyo ulandelelwano lwe-Si-C double atomic layer stacking sequence ye-substrate ukuze yenze i-crystal enye ene-crystal phase efanayo ne-substrate.
(2) Ukukhula kwe-epitaxial okukhawulezayo kufezekiswa ngokungenisa umthombo we-silicon oqulethe i-chlorine. Kwiinkqubo zesiqhelo zokufaka umphunga we-SiC chemical, i-silane kunye ne-propane (okanye i-ethylene) zezona mithombo ziphambili zokukhula. Kwinkqubo yokwandisa izinga lokukhula ngokunyusa izinga lokuhamba komthombo wokukhula, njengoko uxinzelelo oluyinxenye ye-equilibrium yecandelo le-silicon luqhubeka lusanda, kulula ukwenza amaqela e-silicon nge-homogeneous gas phase nucleation, nto leyo enciphisa kakhulu izinga lokusetyenziswa komthombo we-silicon. Ukwenziwa kwamaqela e-silicon kunciphisa kakhulu ukuphuculwa kwesantya sokukhula kwe-epitaxial. Kwangaxeshanye, amaqela e-silicon anokuphazamisa ukukhula kokuhamba kwenyathelo kwaye abangele i-defect nucleation. Ukuze kuthintelwe i-homogeneous gas phase nucleation kunye nokunyusa izinga lokukhula kwe-epitaxial, ukungeniswa kwemithombo ye-silicon esekelwe kwi-chlorine okwangoku yindlela ephambili yokwandisa izinga lokukhula kwe-epitaxial le-4H-SiC.
Izixhobo ze-epitaxial ze-SiC eziyi-1.2 ezingama-200 mm (8-intshi) kunye neemeko zenkqubo
Uvavanyo oluchazwe kweli phepha lwenziwe kwisixhobo se-SiC epitaxial esihambelana ne-150/200 mm (6/8-intshi) esinodonga olushushu oluthe tyaba oluyi-SiC epitaxial esiphuhliswe ngokuzimeleyo yi-48th Institute of China Electronics Technology Group Corporation. Isithando somlilo se-epitaxial sixhasa ukulayishwa kunye nokukhutshwa kwe-wafer ngokuzenzekelayo ngokupheleleyo. Umfanekiso 1 ngumzobo wesicwangciso sesakhiwo sangaphakathi segumbi lokusabela lesixhobo se-epitaxial. Njengoko kubonisiwe kuMfanekiso 1, udonga lwangaphandle lwegumbi lokusabela yintsimbi ye-quartz enomaleko opholisiweyo ngamanzi, kwaye ingaphakathi lentsimbi yigumbi lokusabela elinobushushu obuphezulu, elenziwe yi-thermal insulation carbon felt, i-high-purity special graphite cavity, i-graphite gas-floating base ejikelezayo, njl. Intsimbi yonke ye-quartz igqunywe yi-cylindrical induction coil, kwaye igumbi lokusabela ngaphakathi kwentsimbi lifudunyezwa ngombane ngombane we-medium-frequency induction. Njengoko kubonisiwe kuMfanekiso 1 (b), igesi ethwalayo, igesi yokusabela, kunye negesi yokukhupha i-doping zonke zihamba kumphezulu we-wafer ngendlela ethe tye ye-laminar ukusuka phezulu kwegumbi lokusabela ukuya ezantsi kwegumbi lokusabela kwaye zikhutshwa kwisiphelo segesi yomsila. Ukuqinisekisa ukuhambelana ngaphakathi kwe-wafer, i-wafer ethwalwa sisiseko esintantayo somoya isoloko ijikeleziswa ngexesha lenkqubo.
I-substrate esetyenzisiweyo kolu vavanyo yi-150 mm, 200 mm (6 intshi, 8 intshi) <1120> i-direction 4°off-angle conductive n-type 4H-SiC double-sided polished SiC substrate eveliswe yiShanxi Shuoke Crystal. I-Trichlorosilane (SiHCl3, TCS) kunye ne-ethylene (C2H4) zisetyenziswa njengemithombo ephambili yokukhula kuvavanyo lwenkqubo, phakathi kwazo i-TCS kunye ne-C2H4 zisetyenziswa njengomthombo we-silicon kunye nomthombo we-carbon ngokulandelelana, i-high-purity nitrogen (N2) isetyenziswa njengomthombo we-n-type doping, kwaye i-hydrogen (H2) isetyenziswa njengegesi yokuxuba kunye negesi yokuthwala. Uluhlu lobushushu benkqubo ye-epitaxial yi-1600 ~1660 ℃, uxinzelelo lwenkqubo yi-8×103 ~12×103 Pa, kwaye izinga lokuhamba kwegesi yokuthwala i-H2 yi-100～140 L/min.
1.3 Uvavanyo lwe-Epitaxial wafer kunye nokuchazwa kweempawu
I-Fourier infrared spectrometer (umenzi wezixhobo iThermalfisher, imodeli iS50) kunye ne-mercury probe concentration tester (umenzi wezixhobo iSemilab, imodeli 530L) zisetyenzisiwe ukuchaza i-mean kunye nokusasazwa kobukhulu beleyara ye-epitaxial kunye noxinzelelo lwe-doping; ubukhulu kunye noxinzelelo lwe-doping lwenqaku ngalinye kwileyara ye-epitaxial zimiselwe ngokuthatha amanqaku ecaleni komgca we-diameter adibana nomgca oqhelekileyo we-main reference edge kwi-45° embindini we-wafer kunye nokususwa komphetho we-5 mm. Kwi-wafer ye-150 mm, amanqaku ali-9 athathwe kumgca we-diameter enye (iidayamitha ezimbini zazithe nkqo omnye komnye), kwaye kwi-wafer ye-200 mm, amanqaku angama-21 athathwe, njengoko kubonisiwe kuMfanekiso 2. I-atomic force microscope (umenzi wezixhobo uBruker, imodeli yeDimension Icon) isetyenzisiwe ukukhetha iindawo ze-30 μm×30 μm kwindawo ephakathi kunye nendawo yomphetho (ukususwa komphetho we-5 mm) we-epitaxial wafer ukuvavanya uburhabaxa bomphezulu we-epitaxial layer; Iziphene zomaleko we-epitaxial zilinganiswe kusetyenziswa umvavanyi weziphene zomphezulu (umenzi wezixhobo zaseTshayina Electronics. I-3D imager yayiphawulwe yi-radar sensor (imodeli iMars 4410 pro) evela eKefenghua.
Ixesha leposi: Sep-04-2024