Njengoba kuboniswe ku-Fig. 3, kunezindlela ezintathu ezivelele ezihlose ukunikeza i-SiC single crystal ngekhwalithi ephezulu kanye nokusebenza kahle: i-liquid phase epitaxy (LPE), i-physical vapor transport (PVT), kanye ne-high-temperature chemical vapor deposition (HTCVD). I-PVT inqubo esemisiwe yokukhiqiza i-SiC single crystal, esetshenziswa kabanzi kubakhiqizi abakhulu be-wafer.
Kodwa-ke, zonke lezi zinqubo ezintathu ziyashintsha ngokushesha futhi ziyasungula izinto ezintsha. Akukakwaziwa okwamanje ukuthi iyiphi inqubo ezosetshenziswa kabanzi esikhathini esizayo. Ikakhulukazi, ikristalu elilodwa le-SiC elisezingeni eliphezulu elikhiqizwa ukukhula kwesisombululo ngesivinini esikhulu liye labikwa eminyakeni yamuva nje, ukukhula okukhulu kwe-SiC esigabeni soketshezi kudinga izinga lokushisa eliphansi kunelenqubo yokufakwa kwe-sublimation noma yokufaka, futhi kubonisa ubuhle ekukhiqizeni ama-substrate e-P-type SiC (Ithebula 3) [33, 34].
Isithombe 3: Isimiso sezindlela ezintathu ezivelele zokukhula kwekristalu elilodwa le-SiC: (a) i-epitaxy yesigaba soketshezi; (b) ukuthuthwa komhwamuko ongokoqobo; (c) ukufakwa komhwamuko wamakhemikhali okushisa okuphezulu
Ithebula 3: Ukuqhathaniswa kwe-LPE, i-PVT kanye ne-HTCVD ekukhuliseni amakristalu angawodwa e-SiC [33, 34]
Ukukhula kwesisombululo ubuchwepheshe obujwayelekile bokulungiselela ama-semiconductor ahlanganisiwe [36]. Kusukela ngawo-1960, abacwaningi bazame ukuthuthukisa ikristalu esixazululweni [37]. Uma ubuchwepheshe sebuthuthukisiwe, ukugcwala okuphezulu kwendawo yokukhula kungalawulwa kahle, okwenza indlela yesisombululo ibe ubuchwepheshe obuthembisayo bokuthola ama-ingot ekristalu elilodwa asezingeni eliphezulu.
Ukuze kukhule isixazululo sekristalu elilodwa le-SiC, umthombo we-Si uvela ekuncibilikeni kwe-Si okumsulwa kakhulu kuyilapho i-graphite crucible isebenza ngezinjongo ezimbili: i-heater kanye nomthombo we-solute we-C. Amakristalu elilodwa le-SiC anamathuba amaningi okukhula ngaphansi kwesilinganiso se-stoichiometric esifanele lapho isilinganiso se-C ne-Si siseduze no-1, okubonisa ubuningi obuphansi bokuhluleka [28]. Kodwa-ke, ekucindezelweni komoya, i-SiC ayikhombisi iphuzu lokuncibilika futhi ibola ngqo ngokuhwamuka emazingeni okushisa angaphezu kuka-2,000 °C. Ukuncibilika kwe-SiC, ngokusho kokulindelekile kwethiyori, kungakhiwa kuphela ngaphansi kobunzima obubonakalayo kumdwebo wesigaba se-Si-C binary (Isithombe 4) lapho ngokwe-gradient yokushisa kanye nohlelo lwesisombululo. Uma i-C ephezulu ekuncibilikeni kwe-Si ihluka kusuka ku-1at.% kuya ku-13at.%. I-C supersaturation eqhubayo, izinga lokukhula lishesha, kanti amandla aphansi e-C okukhula yi-C supersaturation elawulwa yi-109 Pa kanye namazinga okushisa angaphezu kuka-3,200 °C. Ingakhiqiza ubuso obubushelelezi [22, 36-38]. Amazinga okushisa aphakathi kuka-1,400 no-2,800 °C, ukuncibilika kwe-C ekuncibilikeni kwe-Si kuyahlukahluka kusuka ku-1at.% kuya ku-13at.%. Amandla ashukumisayo okukhula yi-C supersaturation elawulwa yi-gradient yokushisa kanye nesistimu yesisombululo. Uma i-C supersaturation iphakeme, izinga lokukhula lishesha, kuyilapho i-C supersaturation ephansi ikhiqiza ubuso obubushelelezi [22, 36-38].
Isithombe 4: Umdwebo wesigaba se-binary se-Si-C [40]
Ukufaka i-doping izakhi zensimbi eziguqukayo noma izakhi zomhlaba ezingavamile akugcini nje ngokwehlisa izinga lokushisa lokukhula kodwa kubonakala kuyindlela kuphela yokuthuthukisa kakhulu ukuncibilika kwekhabhoni ekuncibilikeni kwe-Si. Ukwengezwa kwezinsimbi zeqembu lokuguquguquka, njenge-Ti [8, 14-16, 19, 40-52], Cr [29, 30, 43, 50, 53-75], Co [63, 76], Fe [77-80], njll. noma izinsimbi zomhlaba ezingavamile, njenge-Ce [81], Y [82], Sc, njll. ekuncibilikeni kwe-Si kuvumela ukuncibilika kwekhabhoni kudlule u-50at.% esimweni esiseduze nokulingana kwe-thermodynamic. Ngaphezu kwalokho, inqubo ye-LPE ilungele ukufakwa kwe-P-type kwe-SiC, okungatholakala ngokuxuba i-Al ku-
i-solvent [50, 53, 56, 59, 64, 71-73, 82, 83]. Kodwa-ke, ukufakwa kwe-Al kuholela ekwandeni kokumelana kwamakristalu angawodwa e-P-type SiC [49, 56]. Ngaphandle kokukhula kohlobo lwe-N ngaphansi kokufakwa kwe-nitrogen,
Ukukhula kwesisombululo ngokuvamile kuqhubeka emoyeni wegesi ongenawo umoya. Nakuba i-helium (He) ibiza kakhulu kune-argon, iyathandwa izazi eziningi ngenxa ye-viscosity yayo ephansi kanye nokushisa okuphezulu (izikhathi ezingu-8 ze-argon) [85]. Izinga lokufuduka kanye nokuqukethwe kwe-Cr ku-4H-SiC kufana ngaphansi komoya we-He kanye ne-Ar, kufakazelwe ukuthi ukukhula ngaphansi kwe-Heresults kusivinini sokukhula esiphezulu kunokukhula ngaphansi kwe-Ar ngenxa yokushabalaliswa okukhulu kokushisa kwesibambi sembewu [68]. Ivimbela ukwakheka kwe-voids ngaphakathi kwekristalu ekhulile kanye ne-nucleation ezenzakalelayo esixazululweni, khona-ke, i-morphology yobuso obubushelelezi ingatholakala [86].
Leli phepha lethula ukuthuthukiswa, ukusetshenziswa, kanye nezakhiwo zamadivayisi e-SiC, kanye nezindlela ezintathu eziyinhloko zokutshala i-SiC single crystal. Ezigabeni ezilandelayo, kubuyekezwe amasu okukhula kwesisombululo samanje kanye nemingcele ebalulekile ehambisanayo. Ekugcineni, kwaphakanyiswa umbono owaxoxa ngezinselele kanye nemisebenzi yesikhathi esizayo mayelana nokukhula okukhulu kwamakristalu e-SiC single kusetshenziswa indlela yesisombululo.
Isikhathi sokuthunyelwe: Julayi-01-2024