Hona joale,silicon carbide (SiC)ke thermally conductive ceramic material e ithutoang ka mafolofolo lapeng le kantle ho naha. Theoretical thermal conductivity ea SiC e phahame haholo, 'me mefuta e meng ea kristale e ka fihla ho 270W / mK, e seng e ntse e le moetapele har'a lisebelisoa tse sa sebetseng. Ka mohlala, ho sebelisoa ha SiC mocheso conductivity ka bonoa ka thepa substrate ea disebediswa semiconductor, phahameng thermal conductivity ceramic thepa, heaters le lipoleiti futhumatsang bakeng sa ho sebetsa semiconductor, thepa capsule bakeng sa mafura a nyutlelie, le mehele e tiisang khase bakeng sa lipompo tsa compressor.
Kopo easilicon carbidetšimong ea semiconductor
Li-discs le li-fixtures ke lisebelisoa tsa bohlokoa tsa ts'ebetso bakeng sa tlhahiso ea silicon oafer indastering ea semiconductor. Haeba disc e sila e entsoe ka tšepe e entsoeng ka tšepe kapa carbon steel, bophelo ba eona ba tšebeletso bo khutšoanyane 'me coefficient ea eona ea ho atolosa mocheso e kholo. Nakong ea ts'ebetso ea li-wafers tsa silicon, haholo-holo nakong ea ho sila kapa ho bentša ka lebelo le phahameng, ka lebaka la ho senyeha le ho senyeha ha mocheso oa disc ea ho sila, ho thata ho tiisa ho bata le ho ts'oana ha sephaphatha sa silicon. Letlapa la ho sila le entsoeng kali-ceramics tsa silicon carbidee na le moaparo o fokolang ka lebaka la boima ba eona bo phahameng, 'me coefficient ea eona ea ho atolosa mocheso e tšoana hantle le ea li-wafers tsa silicon, kahoo e ka siloa le ho belisoa ka lebelo le phahameng.
Ho phaella moo, ha li-wafers tsa silicon li hlahisoa, li hloka ho fumana phekolo ea mocheso o phahameng oa mocheso 'me hangata li tsamaisoa ka lisebelisoa tsa silicon carbide. Ha li na mocheso ebile ha li senyehe. Khabone e kang taemane (DLC) le litlolo tse ling li ka sebelisoa holim'a metsi ho ntlafatsa ts'ebetso, ho fokotsa tšenyo ea liphaphatha, le ho thibela tšoaetso hore e se ke ea ata.
Ho feta moo, joalo ka moemeli oa lisebelisoa tsa semiconductor tsa moloko oa boraro tse pharaletseng, lisebelisoa tsa silicon carbide single kristale li na le thepa e kang bophara ba bandgap e kholo (makhetlo a ka bang 3 ho feta Si), conductivity e phahameng ea mocheso (makhetlo a ka bang 3.3 a Si kapa makhetlo a 10). ea GaAs), sekhahla se phahameng sa ho falla ha elektronike (hoo e ka bang makhetlo a 2.5 ho feta Si) le sebaka se phahameng sa motlakase (hoo e ka bang 10 makhetlo a Si kapa 5 makhetlo a GaAs). Lisebelisoa tsa SiC li etsa bofokoli ba lisebelisoa tsa lisebelisoa tsa semiconductor tsa setso lits'ebetsong tse sebetsang 'me butle-butle li fetoha tse ka sehloohong tsa li-semiconductors tsa matla.
Tlhokahalo ea li-ceramics tsa silicon carbide tsa conductivity e phahameng ea mocheso e eketsehile haholo
Ka nts'etsopele e tsoelang pele ea mahlale le thekenoloji, tlhoko ea ts'ebeliso ea li-ceramics tsa silicon carbide tšimong ea semiconductor e eketsehile haholo, 'me conductivity e phahameng ea mocheso ke sesupo sa bohlokoa bakeng sa ts'ebeliso ea eona ho likarolo tsa lisebelisoa tsa tlhahiso ea semiconductor. Ka hona, ho bohlokoa ho matlafatsa lipatlisiso mabapi le lirafshoa tse phahameng tsa silicon carbide ceramics. Ho fokotsa bongata ba oksijene ea lattice, ho ntlafatsa boima ba 'mele, le ho laola ka mokhoa o utloahalang ho ajoa ha karolo ea bobeli ka har'a lesela ke mekhoa e ka sehloohong ea ho ntlafatsa mocheso oa mocheso oa li-ceramics tsa silicon carbide.
Hajoale, ho na le lithuto tse fokolang tse mabapi le li-ceramics tsa silicon carbide tse phahameng tsa conductivity naheng ea heso, 'me ho ntse ho na le lekhalo le leholo ha le bapisoa le boemo ba lefatše. Litaelo tsa lipatlisiso tsa nako e tlang li kenyelletsa:
● Matlafatsa mokhoa oa ho lokisetsa lipatlisiso tsa silicon carbide ceramic powder. Ho lokisoa ha bohloeki bo phahameng, bo tlaase ba oksijene silicon carbide phofo ke motheo oa ho lokisetsa li-ceramics tsa silicon carbide tse phahameng tsa conductivity;
● Matlafatsa khetho ea lithuso tsa sintering le lipatlisiso tse amanang le theory;
● Matlafatsa lipatlisiso le nts'etsopele ea lisebelisoa tse phahameng tsa sintering. Ka ho laola mokhoa oa sintering ho fumana microstructure e utloahalang, ke boemo bo hlokahalang ho fumana li-ceramics tse phahameng tsa mocheso oa silicon carbide.
Mehato ea ho ntlafatsa conductivity ea mocheso oa silicon carbide ceramics
Senotlolo sa ho ntlafatsa conductivity ea mocheso oa li-ceramics tsa SiC ke ho fokotsa maqhubu a ho hasanya ha phonon le ho eketsa phonon e bolelang tsela ea mahala. Mocheso oa mocheso oa SiC o tla ntlafatsoa ka katleho ka ho fokotsa porosity le moeli oa lijo-thollo oa li-ceramics tsa SiC, ho ntlafatsa bohloeki ba meeli ea lijo-thollo tsa SiC, ho fokotsa litšila tsa SiC lattice kapa bofokoli ba lattice, le ho eketsa mochine oa phetisetso ea mocheso ho SiC. Hajoale, ho ntlafatsa mofuta le litaba tsa lithuso tsa sintering le kalafo ea mocheso o phahameng oa mocheso ke mehato e ka sehloohong ea ho ntlafatsa conductivity ea mocheso oa li-ceramics tsa SiC.
① Ho ntlafatsa mofuta le litaba tsa lithuso tsa ho bina
Lithuso tse fapaneng tsa sintering hangata li eketsoa ha ho lokisoa li-ceramics tsa SiC tsa conductivity tse phahameng tsa mocheso. Har'a bona, mofuta le litaba tsa lithuso tsa sintering li na le tšusumetso e kholo ho conductivity ea mocheso oa li-ceramics tsa SiC. Ka mohlala, likarolo tsa Al kapa O ho Al2O3 tsamaiso ea lithuso tsa sintering li qhibiliha habonolo ka har'a SiC lattice, e leng se bakang likheo le mefokolo, e leng se lebisang ho eketseha ha maqhubu a ho hasanya ha phonon. Ho phaella moo, haeba litaba tsa lithuso tsa sintering li le tlaase, thepa e thata ho sinter le ho teteka, ha litaba tse phahameng tsa lithuso tsa sintering li tla lebisa ho eketseha ha litšila le mefokolo. Lithuso tse feteletseng tsa mokelikeli oa sintering li ka boela tsa thibela kholo ea lijo-thollo tsa SiC le ho fokotsa tsela ea mahala ea li-phonon. Ka hona, e le ho lokisetsa li-ceramics tsa SiC tsa conductivity tse phahameng tsa mocheso, hoa hlokahala ho fokotsa litaba tsa lithuso tsa sintering ka hohle kamoo ho ka khonehang ha u ntse u kopana le litlhoko tsa sintering density, 'me u leke ho khetha lithuso tsa sintering tseo ho leng thata ho li qhaqha ka lesela la SiC.
* Thermal thepa ea SiC ceramics ha lithuso tse fapaneng tsa sintering li eketsoa
Hajoale, li-ceramics tsa SiC tse hatelitsoeng ka mocheso tse kentsoeng ka BeO e le sesebelisoa sa sintering li na le mocheso o phahameng oa mocheso oa kamore (270W · m-1 · K-1). Leha ho le joalo, BeO ke lintho tse chefo haholo le carcinogenic, 'me ha ea lokela ho sebelisoa ka bongata lilaboratoring kapa masimong a indasteri. Sebaka se tlase ka ho fetesisa sa sistimi ea Y2O3-Al2O3 ke 1760 ℃, e leng thuso e tloaelehileng ea mokelikeli bakeng sa lirafshoa tsa SiC. Leha ho le joalo, kaha Al3 + e qhibiliha habonolo ka har'a letlapa la SiC, ha tsamaiso ena e sebelisoa e le thuso ea sintering, mocheso oa mocheso oa kamore oa SiC ceramics o ka tlaase ho 200W·m-1·K-1.
Lintho tse sa tloaelehang tsa lefats'e tse kang Y, Sm, Sc, Gd le La ha li qhibilihe habonolo ka har'a lattice ea SiC 'me li na le kamano e phahameng ea oksijene, e ka fokotsang ka katleho boemo ba oksijene ea SiC lattice. Ka hona, tsamaiso ea Y2O3-RE2O3 (RE=Sm, Sc, Gd, La) ke sesebelisoa se tloaelehileng sa sintering bakeng sa ho lokisetsa li-conductivity tse phahameng tsa mocheso (> 200W · m-1 · K-1) SiC ceramics. Ho nka thuso ea sintering ea tsamaiso ea Y2O3-Sc2O3 e le mohlala, boleng ba ho kheloha ha ion ba Y3+ le Si4+ bo boholo, 'me tse peli ha li fumane tharollo e tiileng. The solubility ea Sc ka SiC e hloekileng ho 1800 ~ 2600 ℃ e nyenyane, e ka bang (2 ~ 3) × 1017atoms · cm-3.
② Phekolo ea mocheso o phahameng oa mocheso
Phekolo e phahameng ea mocheso oa mocheso oa li-ceramics tsa SiC e thusa ho felisa bofokoli ba lattice, ho kheloha le likhatello tse setseng, ho khothaletsa phetoho ea sebopeho sa lisebelisoa tse ling tsa amorphous ho likristale, le ho fokolisa phello ea ho hasanya ha phonon. Ho phaella moo, phekolo ea mocheso oa mocheso o phahameng o ka ntlafatsa ka katleho kholo ea lijo-thollo tsa SiC, 'me qetellong ea ntlafatsa thepa ea mocheso oa thepa. Ka mohlala, ka mor'a phekolo ea mocheso oa mocheso o phahameng ka 1950 ° C, mocheso oa mocheso oa mocheso oa li-ceramics tsa SiC o ile oa eketseha ho tloha ho 83.03mm2 · s-1 ho ea ho 89.50mm2 · s-1, 'me mocheso oa mocheso oa kamore o ile oa eketseha ho tloha 180.94W·m -1·K-1 ho isa ho 192.17W·m-1·K-1. Phekolo ea mocheso oa mocheso o phahameng ka katleho e ntlafatsa bokhoni ba deoxidation ea thuso ea sintering holim'a SiC holim'a letlapa, 'me e etsa hore kamano pakeng tsa lijo-thollo tsa SiC e be thata haholoanyane. Ka mor'a phekolo ea mocheso o phahameng oa mocheso, mocheso oa mocheso oa kamoreng-mocheso oa mocheso oa li-ceramics tsa SiC o ntlafalitsoe haholo.
Nako ea poso: Oct-24-2024