Uburyo butatu bw'ingenzi bwo gukura kwa kristu ya SiC

Nkuko bigaragara ku Ishusho ya 3, hari uburyo butatu bukomeye bugamije guha SiC crystal imwe ubuziranenge n'imikorere myiza: liquid phase epitaxy (LPE), physical vapor transport (PVT), na high-temperature chemical vapor deposition (HTCVD). PVT ni uburyo buzwi cyane bwo gukora SiC crystal imwe, bukoreshwa cyane mu nganda zikomeye zikora wafer.

Ariko, inzira zose uko ari eshatu zirimo guhinduka vuba kandi zigashya. Ntibirashoboka kumenya inzira izakoreshwa cyane mu gihe kizaza. By’umwihariko, kristu imwe nziza ya SiC ikorwa n’umusaruro ukura ku kigero gishimishije yagaragaye mu myaka ya vuba aha, kwiyongera kwa SiC mu gice cy’amazi bisaba ubushyuhe buri hasi ugereranyije n’uburyo bwo gushyiramo cyangwa gushyiramo, kandi bigaragaza ubuhanga mu gukora substrates za P-type SiC (Imbonerahamwe ya 3) [33, 34].

Igishushanyo cya 3: Ishusho y'uburyo butatu bunini bwo gukura bwa SiC single crystal: (a) epitaxy y'ikigero cy'amazi; (b) gutwara umwuka usanzwe; (c) gushyira umwuka ushyushye cyane mu bushyuhe bwinshi

Imbonerahamwe ya 3: Kugereranya LPE, PVT na HTCVD mu guhinga kristu imwe za SiC [33, 34]

Gukura kw'ibisubizo ni ikoranabuhanga risanzwe ryo gutegura semiconductors [36]. Kuva mu myaka ya 1960, abashakashatsi bagerageje gukora kristu mu gisubizo [37]. Iyo ikoranabuhanga rimaze gutezwa imbere, ubushyuhe bw'ubuso bw'ikura bushobora kugenzurwa neza, bigatuma uburyo bwo gusubiza buhinduka ikoranabuhanga ryiza ryo kubona ingots nziza za kristu imwe.

Ku bijyanye no gukura kwa kristu imwe ya SiC, isoko ya Si ikomoka ku gushonga kwa Si nziza cyane mu gihe icyuma gishyushya gikoreshwa mu bintu bibiri: icyuma gishyushya n'isoko ya C. Kristale imwe ya SiC ishobora gukura munsi y'ikigereranyo cya stoichiometric cyiza iyo igipimo cya C na Si kiri hafi ya 1, bigaragaza ubucucike buri hasi [28]. Ariko, ku muvuduko w'ikirere, SiC nta gice cyo gushonga kigaragaza kandi ibora mu buryo butaziguye binyuze mu guhumeka ku bushyuhe burenga 2.000 °C. Gushonga kwa SiC, dukurikije ibyo abantu biteze, bishobora gukorwa gusa munsi y'ubushyuhe bukabije nk'uko bigaragara ku gishushanyo cya Si-C binary phase (Ishusho ya 4) ku bushyuhe n'uburyo bwo gusubiza. Uko C nyinshi mu gushonga kwa Si ihinduka kuva kuri 1at.% kugeza kuri 13at.%. Gushonga kwa C biyobora, niko umuvuduko wo gukura wihuta, mu gihe imbaraga nke za C z'ikura ari C supersaturation yiganjemo igitutu cya 109 Pa n'ubushyuhe buri hejuru ya 3.200 °C. Ishobora gutuma ubuso burushaho kuba bwiza [22, 36-38]. Ubushyuhe buri hagati ya 1.400 na 2.800 °C, ubushobozi bwo gushonga bwa C mu gushonga kwa Si buhinduka kuva kuri 1at.% kugeza kuri 13at.%. Imbaraga zitera gukura ni C supersaturation igengwa n'ubushyuhe n'uburyo bwo gukemura ikibazo. Uko C supersaturation iba nyinshi, niko umuvuduko wo gukura wihuta, mu gihe C supersaturation iba nkeya ikora ubuso bworoshye [22, 36-38].

Igishushanyo cya 4: Imbonerahamwe y'icyiciro cya kabiri cya Si-C [40]

Gukoresha ibintu by’icyuma bihinduka cyangwa ibintu by’ubutaka budasanzwe ntibigabanya gusa ubushyuhe bw’ikura ahubwo bisa nkaho ari bwo buryo bwonyine bwo kunoza cyane uburyo karuboni ishonga mu gushonga kwa Si. Kongeramo ibyuma by’ubwoko bwa transition, nka Ti [8, 14-16, 19, 40-52], Cr [29, 30, 43, 50, 53-75], Co [63, 76], Fe [77-80], nibindi cyangwa ibyuma by’ubutaka bidasanzwe, nka Ce [81], Y [82], Sc, nibindi. ku gushonga kwa Si bituma gushonga kwa karuboni kurenga 50at.% mu gihe kiri hafi y’uburinganire bwa thermodynamic. Byongeye kandi, tekiniki ya LPE ni nziza kuri P-type doping ya SiC, ishobora kugerwaho hakoreshejwe alloying Al mu
solvent [50, 53, 56, 59, 64, 71-73, 82, 83]. Ariko, gushyiramo Al bituma habaho kwiyongera k’ubudahangarwa bw’uturemangingo duto twa P-type SiC [49, 56]. Uretse gukura kwa N-type hifashishijwe nitrogen doping,

Gukura k'umuti muri rusange bibera mu kirere cy'umwuka udakora neza. Nubwo heliyumu (He) ihenze kurusha argon, ikundwa n'abahanga benshi kubera ko ifite ubushyuhe buke n'ubushyuhe bwinshi (inshuro 8 za argon) [85]. Igipimo cyo kwimuka n'ingano ya Cr muri 4H-SiC bisa munsi y'ikirere cya He na Ar, byagaragaye ko gukura munsi ya Heresults mu gipimo cyo gukura kiri hejuru kuruta gukura munsi ya Ar bitewe n'ubushyuhe bwinshi bw'umubibyi [68]. Ibuza ikorwa ry'imyanda mu gikoresho cyakuze n'ingirabuzimafatizo mu gikoresho, bityo, imiterere y'ubuso bworoshye irashobora kuboneka [86].

Iyi nyandiko yagaragaje iterambere, ikoreshwa, n'imiterere y'ibikoresho bya SiC, hamwe n'uburyo butatu bw'ingenzi bwo guhinga kristu imwe ya SiC. Mu bice bikurikira, hasuzumwe uburyo bwo gukuraho igisubizo n'ibipimo by'ingenzi bihuye nabyo. Amaherezo, hatanzwe igitekerezo cyaganiriye ku mbogamizi n'imirimo y'ejo hazaza ku bijyanye n'izamuka rikomeye rya kristu imwe ya SiC binyuze mu buryo bw'igisubizo.