Njengoko kubonisiwe kumfanekiso wesi-3, kukho iindlela ezintathu eziphambili ezijolise ekuboneleleni i-crystal eyodwa ye-SiC kunye nomgangatho ophezulu kunye nokusebenza kakuhle: i-epitaxy yesigaba solwelo (i-LPE), ukuthuthwa komphunga womzimba (PVT), kunye ne-high-temperature ye-chemical vapor deposition (HTCVD). I-PVT yinkqubo esekwe kakuhle yokuvelisa ikristale enye ye-SiC, esetyenziswa ngokubanzi kubavelisi abakhulu be-wafer.
Nangona kunjalo, zonke ezi nkqubo zintathu zivela ngokukhawuleza kwaye zivelisa izinto ezintsha. Akukenzeki ukuba yeyiphi inkqubo eza kwamkelwa ngokubanzi kwixesha elizayo. Ngokukodwa, i-crystal ye-SiC ekumgangatho ophezulu eveliswe ngokukhula kwesisombululo kwizinga eliphezulu liye laxelwa kwiminyaka yamuva nje, ukukhula kwe-SiC eninzi kwisigaba solwelo kufuna ubushushu obuphantsi kunaleyo ye-sublimation okanye inkqubo yokubeka, kwaye ibonisa ukugqwesa ekuveliseni i-P. -uhlobo lwe-SiC substrates (Itheyibhile 3) [33, 34].
Umzobo 3: Isicwangciso seendlela ezintathu eziphambili ze-SiC enye yokukhula kwekristale: (a) i-epitaxy yesigaba solwelo; (b) ukuthuthwa komphunga obonakalayo; (c) ubushushu obuphezulu bekhemikhali yokubeka umphunga
Itheyibhile 3: Ukuthelekiswa kwe-LPE, i-PVT kunye ne-HTCVD yokukhulisa iikristale ze-SiC enye [33, 34]
Ukukhula kwesisombululo yitekhnoloji eqhelekileyo yokulungiselela i-semiconductors edibeneyo [36]. Ukususela ngo-1960, abaphandi baye bazama ukuphuhlisa ikristale kwisisombululo [37]. Emva kokuba iteknoloji iphuhlisiwe, i-supersaturation yendawo yokukhula inokulawulwa kakuhle, eyenza indlela yesisombululo iteknoloji ethembisayo yokufumana i-ingots ye-crystal eyodwa ephezulu.
Ukukhula kwesisombululo sekristale enye ye-SiC, umthombo we-Si uvela kwi-Si ecocekileyo kakhulu enyibilikayo ngelixa i-graphite crucible isebenza ngeenjongo ezimbini: isifudumezi kunye nomthombo we-C solute. I-crystals enye ye-SiC inokuthi ikhule phantsi komlinganiselo ofanelekileyo we-stoichiometric xa umlinganiselo we-C kunye ne-Si usondele kwi-1, ebonisa ukuxinana kwesiphako esisezantsi [28]. Nangona kunjalo, kuxinzelelo lwe-atmospheric, i-SiC ayibonisi ndawo yokunyibilika kwaye ibola ngokuthe ngqo ngobushushu bobushushu obudlula malunga ne-2,000 °C. I-SiC iyanyibilika, ngokutsho kolindelo lwethiyori, inokubunjwa kuphela phantsi kobunzima bubonwe kwidayagram yesigaba se-binary ye-Si-C (Fig. 4) ukuba ngeqondo lobushushu kunye nenkqubo yesisombululo. I-C ephezulu kwi-Si melt iyahluka ukusuka kwi-1at.% ukuya kwi-13at.%. Ukuqhubela phambili kwe-C supersaturation, ngokukhawuleza izinga lokukhula, ngelixa amandla aphantsi e-C okukhula yi-C supersaturation elawula uxinzelelo lwe-109 Pa kunye namaqondo obushushu angaphezu kwe-3,200 °C. Inokuthi i-supersaturation ivelise indawo egudileyo [22, 36-38] .ubushushu phakathi kwe-1,400 kunye ne-2,800 ° C, ukunyibilika kwe-C kwi-Si melt kuyahluka kwi-1at.% ukuya kwi-13at.%. Amandla okuqhuba ukukhula yi-C supersaturation elawulwa yi-gradient yobushushu kunye nenkqubo yesisombululo. Ukuphakama kwe-C supersaturation, ngokukhawuleza izinga lokukhula, ngelixa i-supersaturation ephantsi ivelisa indawo egudileyo [22, 36-38].
Isazobe 4: Si-C isazobe sesigaba sokubini [40]
I-Doping transition element yentsimbi okanye izinto ezinqabileyo zomhlaba azithobi kuphela ngokufanelekileyo ubushushu bokukhula kodwa zibonakala ziyiyo kuphela indlela yokuphucula kakhulu ukunyibilika kwekhabhoni kwi-Si melt. Ukongezwa kweentsimbi zeqela lenguqu, njengeTi [8, 14-16, 19, 40-52], Cr [29, 30, 43, 50, 53-75], Co [63, 76], Fe [77- 80], njl. okanye iintsimbi zomhlaba ezinqabileyo, ezifana Ce [81], Y [82], Sc, njl ukuya kwi-Si nyibilika ivumela ikhabhoni ukunyibilika kudlule i-50at.% kwimeko ekufutshane ne-thermodynamic equilibrium. Ngapha koko, ubuchule be-LPE bufanelekile kuhlobo lwe-P-doping ye-SiC, enokuzuzwa ngokudibanisa i-Al kwi-doping.
isinyibilikisi [50, 53, 56, 59, 64, 71-73, 82, 83]. Nangona kunjalo, ukufakwa kwe-Al kukhokelela ekwandeni kokumelana ne-P-uhlobo lwe-SiC i-crystals eyodwa [49, 56] .Ngaphandle kokukhula kohlobo lwe-N phantsi kwe-nitrogen doping,
ukukhula kwesisombululo ngokuqhelekileyo kuqhubeka kwimeko yegesi engasebenziyo. Nangona i-helium (He) ibiza kakhulu kune-argon, ithandwa ngabaphengululi abaninzi ngenxa ye-viscosity ephantsi kunye ne-thermal conductivity ephezulu (i-8 amaxesha e-argon) [85]. Izinga lokufuduka kunye nomxholo we-Cr kwi-4H-SiC zifana phantsi kwe-He kunye ne-Aratmospheric, kubonakaliswe ukuba ukukhula phantsi kwe-Heresults kwizinga eliphezulu lokukhula kunokukhula ngaphantsi kwe-Ar ngenxa yokutshatyalaliswa okukhulu kobushushu bomnini wembewu [68]. Uthintela ukwakheka kwe-voids ngaphakathi kwekristale ekhulileyo kunye ne-nucleation ezenzekelayo kwisisombululo, emva koko, i-morphology yomhlaba egudileyo inokufumaneka [86].
Eli phepha lazisa uphuhliso, izicelo, kunye neepropati zezixhobo ze-SiC, kunye neendlela ezintathu eziphambili zokukhulisa i-crystal eyodwa ye-SiC. Kula macandelo alandelayo, iindlela zangoku zokukhula kwesisombululo kunye neeparitha eziphambili ezihambelanayo zahlaziywa. Ekugqibeleni, kwaphakanyiswa umbono owawuxubusha imingeni kunye nemisebenzi yexesha elizayo malunga nokukhula kwe-SiC enye yeekristale ngendlela yesisombululo.
Ixesha lokuposa: Jul-01-2024