Njengoko kubonisiwe kuMfanekiso 3, kukho iindlela ezintathu eziphambili ezijolise ekuboneleleni ngekristale enye yeSiC ngomgangatho ophezulu kunye nokusebenza kakuhle: i-epitaxy yesigaba solwelo (i-LPE), ukuthuthwa komphunga ngokwasemzimbeni (i-PVT), kunye ne-high-temperature chemical vapor deposition (i-HTCVD). I-PVT yinkqubo esele imiselwe kakuhle yokuvelisa ikristale enye yeSiC, esetyenziswa kakhulu kubavelisi abakhulu be-wafer.
Nangona kunjalo, zonke ezi nkqubo zintathu ziyaguquka ngokukhawuleza kwaye ziyatshintsha. Akukakwazi ukuchonga ukuba yeyiphi inkqubo eya kwamkelwa ngokubanzi kwixesha elizayo. Ingakumbi, ikristale enye yeSiC ekumgangatho ophezulu eveliswa kukukhula kwesisombululo ngesantya esikhulu ibikwe kwiminyaka yakutshanje, ukukhula kweSiC ngobuninzi kwisigaba solwelo kufuna ubushushu obuphantsi kunobo benkqubo ye-sublimation okanye ye-deposition, kwaye ibonisa ukugqwesa ekuveliseni ii-substrates ze-P-type SiC (Itheyibhile 3) [33, 34].
Umzobo 3: Isicwangciso seendlela ezintathu eziphambili zokukhula kwekristale enye yeSiC: (a) i-epitaxy yesigaba solwelo; (b) ukuthuthwa komphunga ngokwasemzimbeni; (c) ukufakwa komphunga weekhemikhali obushushu obuphezulu
Itheyibhile 3: Uthelekiso lwe-LPE, i-PVT kunye ne-HTCVD ekukhuliseni iikristale ze-SiC single [33, 34]
Ukukhula kwesisombululo yiteknoloji eqhelekileyo yokulungiselela ii-semiconductors ezidityanisiweyo [36]. Ukususela ngeminyaka yoo-1960, abaphandi baye bazama ukuphuhlisa ikristale kwisisombululo [37]. Nje ukuba iteknoloji iphuhliswe, ukugcwala okuphezulu komphezulu wokukhula kunokulawulwa kakuhle, nto leyo eyenza indlela yesisombululo ibe yiteknoloji ethembisayo yokufumana ii-ingots zekristale enye ezikumgangatho ophezulu.
Ukukhula kwesisombululo sekristale enye yeSiC, umthombo weSi uvela kwi-Si melt ecocekileyo kakhulu ngelixa i-graphite crucible isebenza ngeenjongo ezimbini: i-heater kunye nomthombo we-C solute. Iikristale enye zeSiC zinokukhula phantsi komlinganiselo we-stoichiometric ofanelekileyo xa umlinganiselo we-C kunye ne-Si usondele kwi-1, nto leyo ebonisa uxinano oluphantsi lwe-defect [28]. Nangona kunjalo, kuxinzelelo lomoya, iSiC ayibonisi ndawo yokunyibilika kwaye ibola ngokuthe ngqo nge-vaporization kumaqondo obushushu adlula malunga ne-2,000 °C. Ukunyibilika kweSiC, ngokweembono zethiyori, kunokwakheka kuphela phantsi kobunzima obubonakalayo kwi-Si-C binary phase diagram (Umzobo 4) ukuba kwi-gradient yobushushu kunye nenkqubo yesisombululo. Okukhona i-C ephezulu kwi-Si melt iyahluka ukusuka kwi-1at.% ukuya kwi-13at.%. I-C supersaturation eqhubayo, kokukhona isantya sokukhula sikhawuleza, ngelixa amandla aphantsi e-C okukhula yi-C supersaturation elawulwa yi-109 Pa kunye namaqondo obushushu angaphezu kwe-3,200 °C. Ingakwazi ukuvelisa umphezulu ogudileyo [22, 36-38]. Amaqondo obushushu aphakathi kwe-1,400 kunye ne-2,800 °C, ukunyibilika kwe-C kwi-Si melt kuyahluka ukusuka kwi-1at.% ukuya kwi-13at.%. Amandla aqhuba ukukhula yi-C supersaturation elawulwa yi-gradient yobushushu kunye nenkqubo yesisombululo. Okukhona i-C supersaturation iphezulu, kokukhona isantya sokukhula sikhawuleza, ngelixa i-C supersaturation ephantsi ivelisa umphezulu ogudileyo [22, 36-38].
Umfanekiso 4: Umzobo wesigaba sesibini se-Si-C [40]
Ukuxutywa kwezinto zesinyithi eziguqukayo okanye izinto ezinqabileyo zomhlaba akunciphisi nje kuphela ubushushu bokukhula kodwa kubonakala ngathi yeyona ndlela yokuphucula kakhulu ukunyibilika kwekhabhoni kwi-Si melt. Ukongezwa kweentsimbi zeqela lotshintsho, ezifana ne-Ti [8, 14-16, 19, 40-52], Cr [29, 30, 43, 50, 53-75], Co [63, 76], Fe [77-80], njl. okanye iintsimbi ezinqabileyo zomhlaba, ezifana ne-Ce [81], Y [82], Sc, njl. kwi-Si melt kuvumela ukunyibilika kwekhabhoni ukuba kudlule i-50at.% kwimeko ekufutshane ne-thermodynamic equilibrium. Ngaphezu koko, indlela ye-LPE ilungele ukuxutywa kwe-P-type ye-SiC, enokufezekiswa ngokudibanisa i-Al kwi-alloying.
Isinyibilikisi [50, 53, 56, 59, 64, 71-73, 82, 83]. Nangona kunjalo, ukufakwa kwe-Al kukhokelela ekwandeni kokuxhathisa kweekristale ze-P-type SiC single [49, 56]. Ngaphandle kokukhula kohlobo lwe-N phantsi kokusetyenziswa kwe-nitrogen doping,
Ukukhula kwesisombululo kudla ngokuqhubeka kwi-atmosphere yegesi engangenisi. Nangona i-helium (He) ibiza kakhulu kune-argon, iyathandwa zizazi ezininzi ngenxa ye-viscosity yayo ephantsi kunye nokuqhuba okuphezulu kobushushu (amaxesha asi-8 e-argon) [85]. Izinga lokufuduka kunye nomxholo we-Cr kwi-4H-SiC ziyafana phantsi kwe-atmosphere ye-He kunye ne-Ar, kungqinwe ukuba ukukhula phantsi kwe-Heresults kwizinga eliphezulu lokukhula kunokukhula phantsi kwe-Ar ngenxa yokutshatyalaliswa kobushushu okukhulu kwesibambi sembewu [68]. Ithintela ukwakheka kwe-voids ngaphakathi kwekristale ekhulileyo kunye ne-nucleation ezenzekelayo kwisisombululo, ke ngoko, i-morphology yomphezulu ogudileyo ingafunyanwa [86].
Eli phepha lazisa ngophuhliso, usetyenziso, kunye neempawu zezixhobo zeSiC, kunye neendlela ezintathu eziphambili zokukhulisa ikristale enye yeSiC. Kula macandelo alandelayo, iindlela zokukhula kwesisombululo sangoku kunye neeparameter eziphambili ezihambelanayo zihlolwe. Ekugqibeleni, kwacetyiswa umbono oxoxa ngemingeni kunye nemisebenzi yexesha elizayo malunga nokukhula okukhulu kweekristale enye yeSiC ngendlela yesisombululo.
Ixesha lokuthumela: Julayi-01-2024