Gukura kwa SiC silicon karbide imwe ya kristu

Kuva yavumburwa, karbide ya silicon yakuruye abantu benshi. Carbide ya Silicon igizwe na kimwe cya kabiri cya atome ya Si na C igice cya C, gihujwe na covalent bonds binyuze muri electron zombi zisangira sp3 hybrid orbitals. Mubice byibanze byububiko bwa kirisiti imwe, atome enye za Si zitunganijwe muburyo busanzwe bwa tetrahedral, naho C atom iherereye hagati ya tetrahedron isanzwe. Ibinyuranye, Si atom irashobora kandi gufatwa nkikigo cya tetrahedron, bityo igakora SiC4 cyangwa CSi4. Imiterere ya Tetrahedral. Inkunga ya covalent muri SiC ni ionic cyane, kandi ingufu za silikoni-karubone ni nyinshi cyane, hafi 4.47eV. Bitewe ningufu nke za stacking power, silicon karbide kristal ikora byoroshye polytypes zitandukanye mugihe cyo gukura. Hariho polytypes zirenga 200 zizwi, zishobora kugabanywamo ibyiciro bitatu byingenzi: cubic, hexagonal na trigonal.

Kugeza ubu, uburyo nyamukuru bwo gukura bwa kristu ya SiC burimo Uburyo bwo Gutwara Imyuka Yumubiri (Uburyo bwa PVT), Ubushyuhe bwo hejuru bwa Chemical Vapor Deposition (uburyo bwa HTCVD), Uburyo bwa Liquid Phase, nibindi. Muri byo, uburyo bwa PVT burakuze kandi bukwiranye ninganda umusaruro mwinshi. ?

Uburyo bwitwa PVT bivuga gushyira kristu yimbuto ya SiC hejuru yingenzi, no gushyira ifu ya SiC nkibikoresho fatizo munsi yingenzi. Mu bidukikije bifunze ubushyuhe bwinshi n’umuvuduko muke, ifu ya SiC iragabanuka kandi ikazamuka hejuru munsi yubushyuhe bwa gradient hamwe nubunini butandukanye. Uburyo bwo kuwujyana hafi yimbuto ya kirisiti hanyuma ukongera kuyisubiramo nyuma yo kugera kumurongo urenze urugero. Ubu buryo burashobora kugera kumikurire igenzurwa yubunini bwa SiC na sisitemu yihariye. ?
Ariko, gukoresha uburyo bwa PVT kugirango ukure kristu ya SiC bisaba guhora ukomeza imiterere ikura mugihe cyiterambere ryigihe kirekire, bitabaye ibyo bizatera indwara ya lattice, bityo bigira ingaruka kumiterere ya kristu. Ariko, gukura kwa kristu ya SiC kurangizwa mumwanya ufunze. Hariho uburyo buke bwo kugenzura nuburyo butandukanye, kugenzura inzira rero biragoye.

Muburyo bwo gukura kristu ya SiC kuburyo bwa PVT, uburyo bwo gukura kwintambwe (Intambwe yo Gukura Intambwe) bifatwa nkuburyo nyamukuru bwo gukura gukomeye kumiterere imwe ya kristu.
Ibyuka bya atome ya Si na C atom bizahuza cyane na kirisiti ya kirisiti hejuru ya kink point, aho izahinduka kandi ikura, bigatuma buri ntambwe igenda imbere muburyo bubangikanye. Iyo ubugari bwintambwe hejuru yubuso bwa kirisitu burenze kure ikwirakwizwa ryinzira yubusa ya adatom, umubare munini wa adatom urashobora guteranya, kandi uburyo bubiri bwo gukura bwikirwa bumeze nkuburyo bwo gukura bwashizeho bizasenya uburyo bwo gukura kwintambwe, bikaviramo gutakaza 4H Imiterere ya kristu yamakuru, bivamo inenge nyinshi. Kubwibyo rero, guhindura ibipimo ngenderwaho bigomba kugera kugenzura imiterere yintambwe yubuso, bityo bigahagarika ibisekuruza byinenge za polymorphique, kugera kuntego yo kubona ifishi imwe ya kirisiti, hanyuma amaherezo igategura kristu nziza.

Nkuburyo bwambere bwateye imbere bwa SiC kristaliste yo gukura, uburyo bwo gutwara imyuka yumubiri nuburyo bukoreshwa muburyo bukura bwo gukura kwa kristu ya SiC. Ugereranije nubundi buryo, ubu buryo bufite ibisabwa bike mubikoresho byo gukura, inzira yoroshye yo gukura, kugenzurwa gukomeye, ubushakashatsi bwiterambere bugereranije, kandi bumaze kugera mubikorwa byinganda. Ibyiza byuburyo bwa HTCVD nuko bushobora gukura neza (n, p) hamwe na waferi yuzuye-isukuye cyane, kandi irashobora kugenzura imyuka ya doping kugirango intumbero yabatwara muri wafer ihindurwe hagati ya 3 × 1013 ~ 5 × 1019 / cm3. Ibibi ni urwego rwo hejuru rwa tekiniki kandi umugabane muto ku isoko. Mugihe ikoranabuhanga ryikura rya sisitemu ya SiC ikomeje gukura, bizerekana imbaraga zikomeye mugutezimbere inganda zose za SiC mugihe kiri imbere kandi birashoboka ko ari intambwe nshya mugukura kwa kirisiti ya SiC.