Kubva payakawanikwa, silicon carbide yakakwezva vanhu vakawanda. Silicon carbide inoumbwa nemaatomu eSi hafu nemaatomu eC hafu, ayo akabatana nema covalent bonds kuburikidza nema electron pairs anogovana sp3 hybrid orbitals. Muchikamu che structural unit ye crystal yayo imwe chete, maatomu mana eSi akarongwa muchimiro che tetrahedral chakajairika, uye atomu yeC iri pakati pe tetrahedron yakajairika. Kusiyana neizvi, atomu yeSi inogonawo kuonekwa sepakati pe tetrahedron, nokudaro ichiumba SiC4 kana CSi4. Chimiro che tetrahedral. Chisungo che covalent muSiC chine ionic yakawanda, uye simba re silicon-carbon bond rakakwira zvikuru, rinenge 4.47eV. Nekuda kwesimba re low stacking fault, ma silicon carbide crystals anoumba nyore nyore ma polytype akasiyana-siyana panguva yekukura. Kune ma polytypes anopfuura 200 anozivikanwa, anogona kukamurwa muzvikamu zvitatu zvikuru: cubic, hexagonal uye trigonal.
Parizvino, nzira huru dzekukura dzemakristaro eSiC dzinosanganisira Physical Vapor Transport Method (PVT method), High Temperature Chemical Vapor Deposition (HTCVD method), Liquid Phase Method, nezvimwewo. Pakati padzo, nzira yePVT yakakura uye yakakodzera kugadzirwa kwemaindasitiri.
Nzira inonzi PVT inoreva kuisa makristaro embeu yeSiC pamusoro pechibage, uye kuisa upfu hweSiC sezvinhu zvisina kubikwa pasi pechibage. Munzvimbo yakavharwa ine tembiricha yakakwira uye kumanikidzwa kwakaderera, upfu hweSiC hunonyungudika uye hunofamba huchikwira pasi pechiito chemusiyano wekupisa uye kuenzana. Nzira yekutakura kuenda pedyo nekristaro yembeu wozoidzokorodza mushure mekusvika padanho repamusoro. Nzira iyi inogona kuita kuti kukura kwehukuru hwekristaro yeSiC uye mafomu chaiwo ekristaro kudzorweke.
Zvisinei, kushandisa nzira yePVT kukura makristaro eSiC kunoda kugara uchichengetedza mamiriro ekukura akakodzera panguva yekukura kwenguva refu, zvikasadaro zvinozokonzera kusagadzikana kwelattice, nokudaro zvichikanganisa kunaka kwekristaro. Zvisinei, kukura kwemakristaro eSiC kunopedzwa munzvimbo yakavharwa. Kune nzira shoma dzekutarisa dzinoshanda uye dzakasiyana-siyana, saka kutonga maitiro kwakaoma.
Mukukura kweSiC crystals uchishandisa nzira yePVT, step flow growth mode (Step Flow Growth) inoonekwa senzira huru yekukura kwakasimba kwechimiro chimwe chete chekristaro.
Maatomu eSi neC akaomeswa achabatana nemaatomu ekristaro panzvimbo yekukombama, kwaanozobuda nenyuchi ndokukura, zvichiita kuti danho rega rega rifambe richienderera mberi. Kana upamhi hwedanho riri pamusoro pekristaro hukadarika nzira isina kupararira yeadatomu, huwandu hwakawanda hweadatomu hunogona kuungana, uye nzira yekukura yakafanana nechitsuwa yakagadzirwa ichaparadza nzira yekukura kwedanho, zvichikonzera kurasikirwa neruzivo rwechimiro chekristaro che4H, zvichikonzera zvikanganiso zvakawanda. Nokudaro, kugadziriswa kwema process parameters kunofanirwa kuzadzisa kutonga kwechimiro chedanho repamusoro, nokudaro kuchidzvinyirira kugadzirwa kwezvikanganiso zvepolymorphic, kuzadzisa chinangwa chekuwana chimiro chimwe chete chekristaro, uye pakupedzisira kugadzira makristaro emhando yepamusoro.
Senzira yekutanga yekukura kweSiC crystal, nzira yekufambisa vapor physical ndiyo nzira inonyanya kushandiswa pakukura kweSiC crystals. Kana tichienzanisa nedzimwe nzira, nzira iyi ine zvinodiwa zvishoma zvemidziyo yekukura, nzira iri nyore yekukura, kugona kudzora zvakanyanya, tsvakiridzo yakadzama yekuvandudza, uye yatove nekushandiswa mumaindasitiri. Kubatsira kwenzira yeHTCVD ndeyekuti inogona kukura mawafers anofambisa mhepo (n, p) uye akachena zvakanyanya, uye inogona kudzora huwandu hwedoping kuitira kuti huwandu hwemutakuri muwafer hugadzirisike pakati pe3×1013~5×1019/cm3. Zvakaipa ndezvekuti mutsetse wepamusoro wehunyanzvi uye mugove wakaderera wemusika. Sezvo tekinoroji yekukura kweSiC crystal yemvura ichiramba ichikura, icharatidza mukana mukuru mukusimudzira indasitiri yese yeSiC mune ramangwana uye ingangove nzvimbo itsva yekubudirira mukukura kweSiC crystal.
Nguva yekutumira: Kubvumbi-16-2024