Kemgbe achọpụtara ya, silicon carbide adọtala uche ndị mmadụ. Silicon carbide mejupụtara ọkara atọm Si na ọkara atọm C, nke ejikọtara site na njikọ covalent site na ụzọ elektrọn na-ekerịta orbitals ngwakọ sp3. Na nkeji nhazi nke otu kristal ya, a na-ahazi atọm Si anọ n'usoro tetrahedral nkịtị, atọm C dịkwa n'etiti tetrahedral nkịtị. N'aka nke ọzọ, a pụkwara iwere atọm Si dị ka etiti tetrahedron, si otú a na-emepụta SiC4 ma ọ bụ CSi4. Nhazi tetrahedral. Njikọ covalent na SiC dị oke ionic, ike njikọ silicon-carbon dịkwa elu, ihe dị ka 4.47eV. N'ihi ike ntụpọ dị ala, kristal silicon carbide na-etolite ụdị polytypes dị iche iche n'oge usoro uto. E nwere ihe karịrị ụdị polytypes 200 a maara, nke enwere ike kewaa n'ime ụdị atọ dị mkpa: cubic, hexagonal na trigonal.
Ugbu a, ụzọ isi eto kristal SiC gụnyere Usoro Njem Vapor Physical (usoro PVT), Ndepụta Vapor Chemical Heat High Okpomọkụ (usoro HTCVD), Usoro Mmiri Mmiri, wdg. N'ime ha, usoro PVT ka mma ma dabara adaba maka mmepụta oke ụlọ ọrụ mmepụta ihe.
Usoro a na-akpọ PVT na-ezo aka n'itinye kristal mkpụrụ SiC n'elu ihe mkpuchi ahụ, na itinye ntụ ntụ SiC dị ka ihe eji arụ ọrụ n'ala ihe mkpuchi ahụ. N'ebe mechiri emechi nke okpomọkụ dị elu na nrụgide dị ala, ntụ ntụ SiC na-agbada ma na-aga elu n'okpuru ọrụ nke mgbanwe okpomọkụ na ọdịiche ntinye. Ụzọ isi bufee ya na nso kristal mkpụrụ wee weghachite ya mgbe ọ ruru ọnọdụ juputara na mmiri. Usoro a nwere ike inweta uto a na-achịkwa nke nha kristal SiC na ụdị kristal kpọmkwem.
Agbanyeghị, iji usoro PVT mee ka kristal SiC too chọrọ ịnọgide na-enwe ọnọdụ uto kwesịrị ekwesị mgbe niile n'oge usoro uto ogologo oge, ma ọ bụghị ya, ọ ga-ebute nsogbu lattice, si otú a na-emetụta ịdị mma nke kristal ahụ. Agbanyeghị, uto nke kristal SiC na-agwụ n'ime oghere mechiri emechi. Enwere obere ụzọ nlekota dị irè na ọtụtụ mgbanwe, yabụ njikwa usoro siri ike.
N'usoro ịkụ kristal SiC site na usoro PVT, a na-ewere ọnọdụ uto usoro nzọụkwụ (Uto Nzọụkwụ Nzọụkwụ) dị ka usoro bụ isi maka uto kwụsiri ike nke otu ụdị kristal.
Atọm Si na atọm C ndị a gbazere agbaze ga-ejikọ nke ọma na atọm elu kristal na ebe a na-akpọ kink, ebe ha ga-agbanwe ma too, na-eme ka nzọụkwụ ọ bụla na-asọga n'ihu n'otu oge. Mgbe obosara nzọụkwụ dị n'elu kristal ahụ gafere ụzọ enweghị mgbasa nke adatoms, ọtụtụ adatom nwere ike ịgbakọta, ụdị uto dị ka agwaetiti nke nwere akụkụ abụọ ga-emebi ọnọdụ uto usoro nzọụkwụ, na-ebute mfu nke ozi nhazi kristal 4H, na-ebute ọtụtụ ntụpọ. Ya mere, mgbanwe nke paramita usoro ga-enweta njikwa nke nhazi usoro elu, si otú a na-egbochi mmepụta nke ntụpọ polymorphic, na-emezu ebumnuche nke inweta otu ụdị kristal, na n'ikpeazụ ịkwadebe kristal dị elu.
Dịka ụzọ izizi e mepụtara na SiC kristal, ụzọ mbufe anwụrụ ọkụ anụ ahụ bụ ugbu a ụzọ kachasị ewu ewu maka ịkọ kristal SiC. Ma e jiri ya tụnyere ụzọ ndị ọzọ, usoro a nwere obere ihe achọrọ maka akụrụngwa uto, usoro uto dị mfe, njikwa siri ike, nyocha mmepe zuru oke, ma nwetalarị ngwa ụlọ ọrụ. Uru nke usoro HTCVD bụ na ọ nwere ike itolite wafers na-eduzi (n, p) na wafers semi-insulating dị elu, ma nwee ike ijikwa ntinye doping ka ntinye ihe na-ebu ibu dị na wafer wee nwee ike ịgbanwe n'etiti 3 × 1013 ~ 5 × 1019/cm3. Ihe ndị na-adịghị mma bụ oke teknụzụ dị elu na obere òkè ahịa. Ka teknụzụ uto kristal SiC mmiri mmiri na-aga n'ihu na-etolite, ọ ga-egosi nnukwu ikike n'ịkwalite ụlọ ọrụ SiC niile n'ọdịnihu ma nwee ike ịbụ ebe ọhụrụ na uto kristal SiC.
Oge ozi: Eprel-16-2024