Kemgbe achọpụtara ya, sịlịkọn carbide adọtala uche zuru oke. Silicon carbide mejupụtara ọkara Si atọm na ọkara C atọm, nke ejikọtara site na njikọ covalent site na ụzọ abụọ eletrọn na-ekekọrịta sp3 ngwakọ orbitals. N'ime ngalaba nhazi nke otu kristal ya, a na-ahazi atọm Si anọ n'ụdị tetrahedral mgbe niile, na C atom dị n'etiti etiti tetrahedron oge niile. N'aka nke ọzọ, Si atom nwekwara ike were dị ka etiti tetrahedron, si otú ahụ na-akpụ SiC4 ma ọ bụ CSi4. Ọdịdị tetrahedral. Njikọ covalent dị na SiC dị oke ionic, yana ike njikọ silicon-carbon dị oke elu, ihe dịka 4.47eV. N'ihi mmejọ mmejọ dị ala, kristal silicon carbide na-etolite ụdị polytypes dị mfe n'oge usoro uto. Enwere ihe karịrị ụdị polytypes 200, nke enwere ike kewaa n'ime isi atọ: cubic, hexagonal na trigonal.
Ka ọ dị ugbu a, ụzọ isi eto eto nke kristal SiC gụnyere Physical Vapor Transport Method (PVT method), High Temperature Chemical Vapor Deposition (HTCVD method), Liquid Phase Method, wdg N'ime ha, usoro PVT tozuru oke ma dabara adaba maka ụlọ ọrụ mmepụta ihe. oke mmepụta. ;
Usoro a na-akpọ PVT na-ezo aka n'itinye kristal mkpụrụ osisi SiC n'elu crucible, na itinye SiC ntụ ntụ dị ka ihe onwunwe na ala nke crucible. Na mpaghara mechiri emechi nke oke okpomọkụ na nrụgide dị ala, SiC ntụ ntụ na-ebuli elu ma na-arịgo elu n'okpuru omume nke gradient okpomọkụ na iche iche. Usoro nke ibuga ya na gburugburu kristal mkpụrụ ahụ wee mee ka ọ gbanwee ya mgbe ọ ruru ọnọdụ dị elu. Usoro a nwere ike nweta uto njikwa nke nha kristal SiC na ụdị kristal akọwapụtara. ;
Otú ọ dị, iji usoro PVT na-eto eto kristal SiC na-achọ mgbe niile ịnọgide na-enwe ọnọdụ uto kwesịrị ekwesị n'oge usoro uto ogologo oge, ma ọ bụghị ya, ọ ga-eduga ná nsogbu lattice, si otú ahụ na-emetụta àgwà nke kristal. Otú ọ dị, uto nke kristal SiC na-agwụcha na oghere mechiri emechi. Enwere ụzọ nyocha ole na ole dị irè na ọtụtụ mgbanwe, ya mere njikwa usoro siri ike.
N'ime usoro kristal SiC na-eto eto site na usoro PVT, a na-ahụta usoro nrịba nke uto (Step Flow Growth) dị ka isi usoro maka uto kwụsiri ike nke otu ụdị kristal.
Atọm Si vaporized na C atom ga-akacha mma jikọtara ya na atom elu kristal na ebe kink, ebe ha ga-emebi ma too, na-eme ka nzọụkwụ ọ bụla na-aga n'ihu n'otu aka ahụ. Mgbe obosara nzọụkwụ n'elu kristal karịrị nnọọ mgbasa free ụzọ nke adatoms, a ọnụ ọgụgụ buru ibu nke adatoms nwere ike agglomerate, na akụkụ abụọ àgwàetiti-dị ka uto mode guzobere ga-ebibi nzọụkwụ eruba ibu mode, butere ọnwụ nke 4H. ozi nhazi kristal, na-ebute ọtụtụ ntụpọ. Ya mere, ngbanwe nke usoro usoro ga-enweta njikwa nke nhazi ọkwa elu, si otú ahụ na-egbochi ọgbọ nke ntụpọ polymorphic, nweta nzube nke inweta otu ụdị kristal, na n'ikpeazụ na-akwadebe kristal dị elu.
Dị ka usoro izizi SiC kristal mepere emepe, usoro mbufe ikuku anụ ahụ bụ ugbu a usoro uto kachasị maka itolite kristal SiC. E jiri ya tụnyere ụzọ ndị ọzọ, usoro a nwere ihe ndị dị ala chọrọ maka akụrụngwa na-eto eto, usoro uto dị mfe, njikwa siri ike, nchọpụta mmepe nke ọma, ma nwetaworị ngwa mmepụta ihe. Uru nke usoro HTCVD bụ na ọ nwere ike itolite conductive (n, p) na wafers dị elu nke ọkara mkpuchi mkpuchi, ma nwee ike ịchịkwa ịta doping ka onye na-ebu ibu na wafer na-agbanwe agbanwe n'etiti 3 × 1013 ~ 5 × 1019 / cm3. Ọdịmma ndị ahụ bụ ọnụ ụzọ teknụzụ dị elu yana oke ahịa dị ala. Ka teknụzụ SiC kristal nke mmiri mmiri na-aga n'ihu na-eto eto, ọ ga-egosipụta ikike dị ukwuu n'ịkwalite ụlọ ọrụ SiC niile n'ọdịniihu ma yikarịrị ka ọ ga-abụ isi mmalite ọhụụ na uto kristal SiC.
Oge nzipu: Eprel 16-2024