Okwangoku, ishishini leSiC liyaguquka ukusuka kwi-150 mm (6 intshi) ukuya kwi-200 mm (8 intshi). Ukuze kuhlangatyezwane nemfuno engxamisekileyo yobukhulu obukhulu, obuphezulu beSiC homoepitaxial wafers kushishino, 150mm kunye 200mmI-4H-SiC i-homoepitaxial waferszilungiswe ngempumelelo kwii-substrates zasekhaya kusetyenziswa izixhobo zokukhula ezizimeleyo ze-200mm SiC epitaxial. Inkqubo ye-homoepitaxial efanelekileyo kwi-150mm kunye ne-200mm yaphuhliswa, apho izinga lokukhula kwe-epitaxial linokuba likhulu kune-60um / h. Ngelixa udibana ne-epitaxy enesantya esiphezulu, umgangatho we-epitaxial wafer ugqwesile. Ubukhulu obufanayo be-150 mm kunye ne-200 mmI-SiC epitaxial wafersinokulawulwa ngaphakathi kwe-1.5%, ukufana koxinaniso kungaphantsi kwe-3%, ukuxinwa kwesiphako esibulalayo kungaphantsi kwe-0.3 particles / cm2, kunye ne-epitaxial surface roughness root mean square Ra ingaphantsi kwe-0.15nm, kwaye zonke izibonakaliso zenkqubo engundoqo zikhona. inqanaba eliphezulu loshishino.
I-Silicon Carbide (SiC)ungomnye wabameli bezixhobo ze-semiconductor zesizukulwana sesithathu. Ineempawu zokomelela kwebala lokuqhekeka okuphezulu, ukuhanjiswa kwe-thermal okugqwesileyo, i-electron saturation drift velocity enkulu, kunye nokuxhathisa okuqinileyo kwimitha. Yandise kakhulu amandla okusebenza kwamandla ezixhobo zamandla kwaye inokuhlangabezana neemfuno zenkonzo yesizukulwana esilandelayo sombane wezixhobo zombane kwizixhobo ezinamandla amakhulu, ubungakanani obuncinci, ubushushu obuphezulu, imitha ephezulu kunye nezinye iimeko ezigqithisileyo. Inokunciphisa indawo, ukunciphisa ukusetyenziswa kwamandla kunye nokunciphisa iimfuno zokupholisa. Izise iinguqu eziguqukayo kwizithuthi zamandla amatsha, ezothutho zikaloliwe, iigridi ezikrelekrele kunye namanye amabala. Ke ngoko, i-silicon carbide semiconductors iye yabonwa njengeyona nto ifanelekileyo eya kukhokelela kwisizukulwana esilandelayo sezixhobo zombane ezinamandla aphezulu. Kwiminyaka yakutshanje, ngenxa yenkxaso yomgaqo-nkqubo wesizwe wophuhliso loshishino lwesemiconductor lwesizukulwana sesithathu, uphando kunye nophuhliso kunye nolwakhiwo lwenkqubo yoshishino lwesixhobo se-SiC eyi-150 mm sele igqityiwe eTshayina, kwaye ukhuseleko lwekhonkco lweshishini luye lwagqitywa. iqinisekisiwe ngokwesiseko. Ke ngoko, ugqaliselo lweshishini luye lwatshintsha ngokuthe ngcembe kulawulo lweendleko kunye nokuphucula ukusebenza kakuhle. Njengoko kuboniswe kwiThebhile 1, xa kuthelekiswa ne-150 mm, i-200 mm SiC inezinga eliphezulu lokusetyenziswa kwe-edge, kwaye ukukhutshwa kwee-chips ze-wafer single kunokunyuswa malunga namaxesha e-1.8. Emva kokuba iteknoloji ivuthwa, iindleko zokuvelisa i-chip enye zingancitshiswa ngama-30%. Ukuphumelela kweteknoloji ye-200 mm yindlela ethe ngqo "yokunciphisa iindleko kunye nokwandisa ukusebenza kakuhle", kwaye ikwayisitshixo kwishishini lelizwe lam le-semiconductor ukuba "liqhube ngokuhambelanayo" okanye "ukukhokela".
Yahlukile kwinkqubo yesixhobo seSi,Izixhobo zamandla ze-SiC semiconductorzonke zicutshungulwa kwaye zilungiswe ngeemaleko ze-epitaxial njengelitye lembombo. Ii-wafers ze-Epitaxial ziyimfuneko esisiseko yezixhobo zamandla ze-SiC. Umgangatho we-epitaxial layer ichaza ngokuthe ngqo isivuno sesixhobo, kwaye iindleko zayo zithatha i-20% yeendleko zokuvelisa i-chip. Ke ngoko, ukukhula kwe-epitaxial likhonkco elibalulekileyo eliphakathi kwizixhobo zamandla ze-SiC. Umda ophezulu wenqanaba lenkqubo ye-epitaxial unqunywe ngezixhobo ze-epitaxial. Okwangoku, idigri ye-localization ye-150mm ye-SiC yezixhobo ze-epitaxial e-China iphezulu, kodwa i-layout iyonke ye-200mm isemva kwinqanaba lamazwe ngamazwe ngaxeshanye. Ngoko ke, ukuze kulungiswe iimfuno ezingxamisekileyo kunye neengxaki zeebhotile zobukhulu obukhulu, umgangatho ophezulu we-epitaxial ukuveliswa kwemveliso yophuhliso lwemveliso ye-semiconductor yasekhaya yesizukulwana sesithathu, eli phepha lazisa izixhobo ze-epitaxial ze-200 mm ze-SiC eziphuhliswe ngempumelelo kwilizwe lam. kwaye ufunda inkqubo ye-epitaxial. Ngokulungisa iiparameters zenkqubo ezifana nobushushu benkqubo, isantya sokuhamba kwegesi ye-carrier, i-C / Si ratio, njl., i-concentration uniformity <3%, ubukhulu be-non-uniformity <1.5%, i-roughness Ra <0.2 nm kunye ne-fatal defect density <0.3 grains /cm2 ye-150 mm kunye ne-200 mm ye-SiC epitaxial wafers ene-200 mm eyenziwe ngokuzimeleyo ye-silicon carbide epitaxial furnace ifunyenwe. Umgangatho wenkqubo yesixhobo unokuhlangabezana neemfuno zokulungiswa kwesixhobo samandla esikumgangatho ophezulu weSiC.
1 Linge
1.1 Umgaqo-siseko weSiC epitaxialinkqubo
Inkqubo yokukhula kwe-homoepitaxial ye-4H-SiC ikakhulu ibandakanya amanyathelo angundoqo e-2, oko kukuthi, i-high-temperature in-situ etching ye-4H-SiC substrate kunye ne-homogeneous chemical vapor deposition process. Eyona njongo iphambili ye-substrate in-situ etching kukususa umonakalo ongaphantsi komhlaba we-substrate emva kokupolisha kwe-wafer, ulwelo olushiyekileyo lokupholisha, amasuntswana kunye ne-oxide layer, kunye nesakhiwo senyathelo eliqhelekileyo le-athomu linokwakheka kumphezulu we-substrate ngokucofa. I-in-situ etching idla ngokuqhutyelwa kwi-atmosphere ye-hydrogen. Ngokweemfuno zangempela zenkqubo, inani elincinci legesi elincedisayo lingaphinda lifakwe, njenge-hydrogen chloride, ipropane, i-ethylene okanye i-silane. Ubushushu be-i-situ hydrogen etching ngokubanzi bungaphezulu kwe-1 600 ℃, kwaye uxinzelelo lwegumbi lokusabela lulawulwa ngokubanzi ngezantsi kwe-2 × 104 Pa ngexesha lenkqubo yokubhala.
Emva kokuba umphezulu we-substrate uvulwe yi-in-situ etching, ingena kwinkqubo yokubeka umphunga wekhemikhali yobushushu obuphezulu, oko kukuthi, umthombo wokukhula (ofana ne-ethylene/propane, TCS/silane), umthombo wedoping (n-type doping source nitrogen , i-p-type doping source TMAl), kunye negesi encedisayo efana ne-hydrogen chloride ithuthelwa kwigumbi lokuphendula ngokuhamba okukhulu kwegesi ye-carrier (ngokuqhelekileyo i-hydrogen). Emva kokuba igesi iphendule kwigumbi lokuphendula lobushushu obuphezulu, inxalenye yesandulela isabela ngokwekhemikhali kunye ne-adsorbs kwindawo enqabileyo, kunye ne-4H-SiC ye-epitaxial layer ye-crystal eyodwa ene-concentration ethile ye-doping, ubukhulu obuthile, kunye nomgangatho ophezulu. kwi-substrate surface usebenzisa i-single-crystal 4H-SiC substrate njenge template. Emva kweminyaka yokuhlolwa kwezobugcisa, iteknoloji ye-4H-SiC ye-homoepitaxial ikhulile ngokusisiseko kwaye isetyenziswa ngokubanzi kwimveliso yamashishini. Iteknoloji ye-homoepitaxial ye-4H-SiC esetyenziswa kakhulu kwihlabathi ineempawu ezimbini eziqhelekileyo:
(1) Ukusebenzisa i-off-axis (ngokunxulumene <0001> i-crystal plane, ukuya kwi- <11-20> i-crystal direction) i-oblique cut substrate njenge-template, i-high-purity single-crystal 4H-SiC epitaxial layer ngaphandle kokungcola. idiphozithwe kwi-substrate ngendlela yokukhula kwenyathelo lokukhula. Ekuqaleni kwe-4H-SiC ukukhula kwe-homoepitaxial kusetyenziswa i-crystal substrate efanelekileyo, oko kukuthi, <0001> Si indiza yokukhula. Ubuninzi bamanyathelo e-athomu kumphezulu we-crystal substrate ephilileyo iphantsi kwaye i-terraces ibanzi. Ukukhula kwe-nucleation yamacala amabini kulula ukuba kwenzeke ngexesha lenkqubo ye-epitaxy ukwenza i-3C crystal SiC (3C-SiC). Ngokusikwa kwe-off-axis, uxinano oluphezulu, amanyathelo e-athom yobubanzi obumxinwa bomhlaba angangeniswa kumphezulu we-4H-SiC <0001> substrate, kunye ne-adsorbed precursor inokufikelela ngokufanelekileyo kwindawo yenyathelo leathom kunye namandla aphantsi aphantsi komhlaba ngokusasazwa komphezulu. . Kwinqanaba, i-athom ye-athom / indawo yokudibanisa iqela lemolekyuli yodwa, ngoko kwindlela yokukhula kwenyathelo, i-epitaxial layer inokuzuza ngokugqibeleleyo i-Si-C kabini umaleko we-athomu yokulandelelana kwe-substrate ukwenza ikristale enye kunye nekristale efanayo. isigaba njenge substrate.
(2) Ukukhula kwe-epitaxial ngesantya esiphezulu kufezekiswa ngokuzisa umthombo we-silicon ene-chlorine. Kwiinkqubo eziqhelekileyo ze-SiC zemichiza yokubeka umphunga, i-silane kunye nepropane (okanye i-ethylene) yimithombo ephambili yokukhula. Kwinkqubo yokunyusa izinga lokukhula ngokunyusa izinga lokukhula komthombo wokukhula, njengoko ukulingana koxinzelelo lwenxalenye ye-silicon kuqhubeka ukunyuka, kulula ukwenza amaqela e-silicon nge-homogeneous gas phase nucleation, enciphisa kakhulu izinga lokusetyenziswa kwe-silicon. umthombo wesilicon. Ukwenziwa kwamaqela e-silicon kunciphisa kakhulu ukuphuculwa kwezinga lokukhula kwe-epitaxial. Kwangelo xesha, amaqela e-silicon anokuphazamisa ukukhula kwamanyathelo kwaye abangele i-nucleation yesiphene. Ukuze ugweme i-homogeneous gas phase nucleation kunye nokwandisa izinga lokukhula kwe-epitaxial, ukuqaliswa kwemithombo ye-silicon esekelwe kwi-chlorine okwangoku yindlela eqhelekileyo yokunyusa izinga lokukhula kwe-epitaxial ye-4H-SiC.
1.2 200 mm (8-intshi) izixhobo ze-SiC epitaxial kunye neemeko zenkqubo
Imifuniselo echazwe kweli phepha zonke zaqhutywa kwi-150/200 mm (6/8-intshi) ehambelanayo monolithic othe tyaba hot udonga SiC izixhobo epitaxial ngokuzimeleyo zaphuhliswa 48th Institute of China Electronics Technology Group Corporation. Isithando somlilo se-epitaxial sixhasa ngokupheleleyo ukulayishwa kwe-wafer kunye nokukhulula. Umzobo we-1 ngumzobo oqingqiweyo wesakhiwo sangaphakathi segumbi lokuphendula lezixhobo ze-epitaxial. Njengoko kubonisiwe kwi-Figure 1, udonga lwangaphandle lwegumbi lokuphendula yintsimbi ye-quartz kunye ne-interlayer epholileyo yamanzi, kwaye ingaphakathi lentsimbi ligumbi lokuphendula lobushushu obuphezulu, elihlanganiswe ne-thermal insulation carbon feel, high-purity. I-graphite cavity ekhethekileyo, isiseko segesi ejikelezayo yegraphite, njl njl. Intsimbi ye-quartz yonke igqunywe nge-cylindrical induction coil, kunye negumbi lokuphendula ngaphakathi kwentsimbi lifudunyezwa ngombane wombane ophakathi-frequency induction power. Njengoko kubonisiwe kuMfanekiso 1 (b), irhasi ethwalayo, irhasi yokusabela, kunye nerhasi yedoping zonke zihamba ngaphaya komgangatho osicaba kwindawo ethe tyaba yokuqukuqela kwelaminar ukusuka phezulu kumsinga wegumbi lokusabela ukuya kumazantsi omlambo wegumbi lokusabela kwaye zikhutshiwe emsileni. ukuphela kwegesi. Ukuqinisekisa ukuhambelana phakathi kwe-wafer, i-wafer eqhutywe yisiseko somoya esijikelezayo sihlala sijikeleza ngexesha lenkqubo.
I-substrate esetyenzisiweyo kuvavanyo yintengiso ye-150 mm, i-200 mm (i-6 intshi, i-8 intshi) <1120> isalathiso se-4 ° off-angle conductive n-uhlobo lwe-4H-SiC ephindwe kabini epholisiweyo ye-SiC substrate eveliswe nguShanxi Shuoke Crystal. I-Trichlorosilane (i-SiHCl3, i-TCS) kunye ne-ethylene (i-C2H4) isetyenziswa njengemithombo ephambili yokukhula kwinkqubo yovavanyo, phakathi kwayo i-TCS kunye ne-C2H4 zisetyenziswa njengomthombo we-silicon kunye nomthombo wekhabhoni ngokulandelanayo, i-nitrogen ephezulu ecocekileyo (N2) isetyenziswa njenge-n- uhlobo lwedoping source, kunye nehydrogen (H2) isetyenziswa njengerhasi yodilution kunye nerhasi yokuthwala. Uluhlu lweqondo lokushisa lwenkqubo ye-epitaxial yi-1 600 ~ 1 660 ℃, uxinzelelo lwenkqubo yi-8 × 103 ~ 12 × 103 Pa, kunye ne-H2 carrier gas flow rate yi-100～140 L / min.
1.3 Uvavanyo lwe-Epitaxial wafer kunye neempawu
I-Fourier infrared spectrometer (umenzi wezixhobo i-Thermalfisher, imodeli iS50) kunye nomvavanyi wogxininiso wemekyuri (umenzi wezixhobo iSemilab, imodeli 530L) zisetyenziselwe ukubonisa intsingiselo kunye nokusasazwa kobunzima be-epitaxial kunye nokuxinana kwedoping; ubukhulu kunye noxinzelelo lwe-doping yenqaku ngalinye kwi-epitaxial layer yamiselwa ngokuthatha amanqaku kunye nomgca wedayamitha unqumla umgca oqhelekileyo we-reference edge kwi-45 ° kumbindi we-wafer kunye nokususwa komphetho we-5 mm. Kwi-wafer ye-150 mm, amanqaku angama-9 athathwe kunye nomgca we-diameter enye (i-diameters ezimbini zi-perpendicular omnye komnye), kunye ne-200 mm wafer, amanqaku angama-21 athathwe, njengoko kuboniswe kuMfanekiso 2. I-microscope yamandla e-athomu (umenzi wezixhobo). I-Bruker, imodeli ye-Icon ye-Dimension) yayisetyenziselwa ukukhetha i-30 μm × 30 μm indawo kwindawo ephakathi kunye nommandla wecala (ukususwa komphetho we-5 mm) we-epitaxial wafer ukuvavanya ubuninzi bomgangatho we-epitaxial layer; iziphene zomaleko we-epitaxial zilinganiswe kusetyenziswa umhloli wesiphako somphezulu (umenzi wezixhobo ze-China Electronics Umzobo we-3D ubonakaliswe yinzwa ye-radar (imodeli ye-Mars 4410 pro) evela e-Kefenghua.
Ixesha lokuposa: Sep-04-2024