Okwamanje,i-silicon carbide (SiC)i-thermal conductive ceramic material efundiswa ngenkuthalo ekhaya nakwamanye amazwe. I-Theory conductivity ye-thermal conductivity ye-SiC iphezulu kakhulu, futhi amanye amafomu e-crystal angafinyelela ku-270W / mK, osevele engumholi phakathi kwezinto ezingezona zokuqhuba. Isibonelo, ukusetshenziswa kwe-SiC conductivity eshisayo kungabonakala ezintweni ze-substrate zamadivayisi we-semiconductor, izinto ze-ceramic conductivity ezishisayo eziphezulu, ama-heaters namapuleti okushisa okucubungula kwe-semiconductor, izinto ze-capsule zamafutha enuzi, nezindandatho zokuvala igesi zamaphampu we-compressor.
Isicelo sei-silicon carbideemkhakheni we-semiconductor
Ama-discs okugaya kanye nezakhiwo kuyimishini ebalulekile yenqubo yokukhiqizwa kwe-silicon wafer embonini ye-semiconductor. Uma i-disc yokugaya yenziwe nge-cast iron noma i-carbon steel, impilo yayo yesevisi ifushane futhi i-coefficient yayo yokwandisa okushisayo inkulu. Ngesikhathi sokucutshungulwa kwama-wafers e-silicon, ikakhulukazi ngesikhathi sokugaya noma ukupholishwa ngesivinini esikhulu, ngenxa yokuguga nokuguquka okushisayo kwediski yokugaya, ukuqina nokufana kwe-silicon wafer kunzima ukukuqinisekisa. I-disc yokugaya eyenziwei-silicon carbide ceramicsinokugqoka okuphansi ngenxa yokuqina kwayo okuphezulu, futhi i-coefficient yayo yokwandisa ukushisa ngokuyisisekelo iyafana neyama-silicon wafers, ngakho ingagaywa futhi ipholishwe ngesivinini esikhulu.
Ukwengeza, lapho ama-wafers e-silicon ekhiqizwa, adinga ukuphathwa ngokushisa okushisayo futhi avame ukuhanjiswa kusetshenziswa izinto ze-silicon carbide. Azikwazi ukumelana nokushisa futhi azikonakali. Ikhabhoni efana nedayimane (i-DLC) nezinye izinto zokumboza zingafakwa phezulu ukuze kuthuthukiswe ukusebenza, kuncishiswe umonakalo ocekeceke, futhi kuvinjwe ukubhebhetheka kokungcola.
Ngaphezu kwalokho, njengommeleli wesizukulwane sesithathu se-wide-bandgap semiconductor materials, i-silicon carbide single crystal materials inezakhiwo ezifana nobubanzi be-bandgap enkulu (cishe izikhathi ezi-3 kuno-Si), ukushisa okuphezulu kwe-thermal (cishe izikhathi ezingu-3.3 kune-Si noma izikhathi ezingu-10 ama-GaAs), izinga eliphezulu lokufuduka kwama-electron (cishe izikhathi ezingu-2.5 kunesika-Si) kanye nenkundla kagesi ephukile (cishe Izikhathi eziyi-10 kunesika-Si noma izikhathi ezi-5 kulezo ze-GaAs). Amadivayisi e-SiC akha amaphutha ezinto ezibonakalayo ze-semiconductor ezisetshenziswayo ezisetshenziswayo futhi kancane kancane aphenduka inkambiso yama-semiconductors amandla.
Isidingo se-thermal conductivity ephezulu ye-silicon carbide ceramics senyuke kakhulu
Ngokuthuthuka okuqhubekayo kwesayensi nobuchwepheshe, isidingo sokusetshenziswa kwe-silicon carbide ceramics emkhakheni we-semiconductor sikhule kakhulu, futhi ukuqhutshwa kwe-thermal ephezulu kuyinkomba ebalulekile yokusetshenziswa kwayo ezingxenyeni zemishini yokukhiqiza ye-semiconductor. Ngakho-ke, kubalulekile ukuqinisa ucwaningo nge-thermal conductivity silicon carbide ceramics. Ukunciphisa okuqukethwe kwe-oksijini ye-lattice, ukuthuthukisa ukuminyana, nokulawula ngokunengqondo ukusatshalaliswa kwesigaba sesibili ku-lattice yizindlela eziyinhloko zokuthuthukisa ukuqhutshwa kokushisa kwe-silicon carbide ceramics.
Njengamanje, kunezifundo ezimbalwa mayelana ne-thermal conductivity silicon carbide ceramics ezweni lami, futhi lisekhona igebe elikhulu uma liqhathaniswa nezinga lomhlaba. Izikhombisi-ndlela zocwaningo lwangomuso zihlanganisa:
● Qinisa ucwaningo lwenqubo yokulungiselela i-silicon carbide ceramic powder. Ukulungiswa kokuhlanzeka okuphezulu, okuphansi kwe-oksijeni ye-silicon carbide powder kuyisisekelo sokulungiswa kwe-thermal conductivity silicon carbide ceramics;
● Ukuqinisa ukukhethwa kwezinsiza-kufunda kanye nocwaningo lwethiyori oluhlobene;
●Qinisekisa ucwaningo kanye nokuthuthukiswa kwemishini ye-sintering ephezulu. Ngokulawula inqubo ye-sintering ukuze uthole i-microstructure enengqondo, kuyisimo esidingekayo ukuthola i-thermal conductivity silicon carbide ceramics.
Izinyathelo zokuthuthukisa ukusebenza okushisayo kwe-silicon carbide ceramics
Isihluthulelo sokuthuthukisa i-thermal conductivity ye-ceramics ye-SiC ukunciphisa imvamisa yokusakazwa kwe-phonon nokwandisa indlela ye-phonon isho indlela yamahhala. I-thermal conductivity ye-SiC izothuthukiswa ngempumelelo ngokunciphisa i-porosity kanye nokuminyana komngcele wokusanhlamvu we-SiC ceramics, ukuthuthukisa ukuhlanzeka kwemingcele yezinhlamvu ze-SiC, ukunciphisa ukungcola kwe-SiC lattice noma ukukhubazeka kwe-lattice, nokwandisa umthwali wokudlulisa ukushisa kokugeleza ku-SiC. Njengamanje, ukuthuthukisa uhlobo nokuqukethwe kwezinsiza ze-sintering kanye nokwelashwa kokushisa okuphezulu yizinyathelo eziyinhloko zokuthuthukisa ukuqhutshwa kokushisa kwe-SiC ceramics.
① Ukuthuthukisa uhlobo nokuqukethwe kwezinsiza zokucula
Izinsiza ezihlukahlukene ze-sintering zivame ukungezwa lapho kulungiswa ama-ceramics e-SiC conductivity ashisayo. Phakathi kwazo, uhlobo nokuqukethwe kwezinsiza ze-sintering kunethonya elikhulu ekuphatheni okushisayo kwe-SiC ceramics. Isibonelo, izakhi ze-Al noma ze-O ohlelweni lwe-Al2O3 lwezinsiza zokuhlanganisa zincibilika kalula ku-SiC lattice, okuholela ezikhaleni nasezikhungweni, okuholela ekwandeni kwemvamisa yokusakazwa kwephonon. Ukwengeza, uma okuqukethwe kwezinsiza ze-sintering kuphansi, izinto ezibonakalayo zinzima ukucwilisa futhi zigxilise, kuyilapho okuqukethwe okuphezulu kwezinsiza ze-sintering kuzoholela ekwandeni kokungcola kanye nokukhubazeka. Izinsiza ze-sintering zesigaba soketshezi ezeqile zingase futhi zivimbele ukukhula kwezinhlamvu ze-SiC futhi zinciphise indlela yamahhala yamaphononi. Ngakho-ke, ukuze kulungiswe i-SiC ceramics ye-conductivity ephezulu eshisayo, kuyadingeka ukunciphisa okuqukethwe kwezinsiza ze-sintering ngangokunokwenzeka ngenkathi uhlangabezana nezidingo ze-sintering density, futhi uzame ukukhetha izinsiza ze-sintering okunzima ukuzincibilika ku-lattice ye-SiC.
*Izindawo ezishisayo zama-ceramics we-SiC lapho kunezinsiza ezihlukile zokuhlanganisa
Okwamanje, ama-ceramics e-SiC acindezelwe okushisayo afakwe nge-BeO njengosizo lwe-sintering ane-conductivity ephezulu yezinga lokushisa lokushisa (270W · m-1·K-1). Kodwa-ke, i-BeO iyimpahla enobuthi obuphezulu kanye ne-carcinogenic, futhi ayifanele ukusetshenziswa kabanzi kumalabhorethri noma izimboni. Indawo ephansi ye-eutectic yohlelo lwe-Y2O3-Al2O3 ngu-1760 ℃, okuwusizo oluvamile lwesigaba soketshezi se-sintering yezitsha zobumba ze-SiC. Kodwa-ke, njengoba i-Al3+ incibilika kalula ku-lattice ye-SiC, lapho lesi simiso sisetshenziswa njengosizo lwe-sintering, ukushisa kwegumbi lokushisa kwe-SiC ceramics kungaphansi kuka-200W · m-1·K-1.
Izakhi zomhlaba ezingavamile ezifana ne-Y, Sm, Sc, Gd kanye ne-La azincibiliki kalula ku-SiC lattice futhi zinokusondelana komoya-mpilo okuphezulu, okunganciphisa ngempumelelo okuqukethwe komoyampilo we-SiC lattice. Ngakho-ke, isistimu ye-Y2O3-RE2O3 (RE=Sm, Sc, Gd, La) iwusizo oluvamile lwe-sintering lokulungiselela ukuguquguquka okuphezulu kwe-thermal (>200W · m-1·K-1) izitsha zobumba ze-SiC. Uma sithatha i-Y2O3-Sc2O3 uhlelo losizo lwe-sintering njengesibonelo, inani lokuchezuka kwe-ion lika-Y3+ ne-Si4+ likhulu, futhi okubili akutholi isisombululo esiqinile. I-solubility ye-Sc ku-SiC emsulwa kokuthi 1800~2600℃ incane, cishe (2~3)×1017atoms·cm-3.
② Ukwelashwa kokushisa okuphezulu
Ukwelashwa kokushisa okuphezulu kwezinga lokushisa le-SiC ceramics kulungele ukuqeda ukukhubazeka kwe-lattice, ukugudluzwa nokucindezeleka okusalayo, ukukhuthaza ukuguqulwa kwesakhiwo sezinto ezithile ze-amorphous kumakristalu, kanye nokwenza buthaka umphumela wokuhlakazeka kwephonon. Ngaphezu kwalokho, ukwelashwa kokushisa okuphezulu kungakhuthaza ngokuphumelelayo ukukhula kwezinhlamvu ze-SiC, futhi ekugcineni kuthuthukise izakhiwo ezishisayo zezinto ezibonakalayo. Isibonelo, ngemva kokwelashwa kokushisa okushisisa kakhulu ngo-1950 ° C, i-thermal diffusion coefficient ye-ceramics ye-SiC inyuke isuka ku-83.03mm2 · s-1 yaya ku-89.50mm2 · s-1, futhi ukuhanjiswa kwe-thermal kwegumbi kukhuphuke kusuka ku-180.94W·m -1·K-1 kuya ku-192.17W·m-1·K-1. Ukwelashwa kokushisa okunokushisa okuphezulu kuthuthukisa ngempumelelo ikhono le-deoxidation losizo lwe-sintering endaweni ye-SiC kanye ne-lattice, futhi kwenza ukuxhumana phakathi kwezinhlamvu ze-SiC kuqine. Ngemuva kokwelashwa kokushisa okuphezulu, ukuhanjiswa kwe-thermal yegumbi le-SiC ceramics kuye kwathuthukiswa kakhulu.
Isikhathi sokuthumela: Oct-24-2024