Ngoku,i-silicon carbide (SiC)sisixhobo se-ceramic esiqhutywa nge-thermally esifundwa ngenkuthalo ekhaya nakwamanye amazwe. I-theoretical conductivity ye-thermal ye-SiC iphezulu kakhulu, kwaye ezinye iifom ze-crystal zinokufikelela kwi-270W / mK, esele iyinkokeli phakathi kwezinto ezingezizo. Ngokomzekelo, ukusetyenziswa kwe-SiC ye-thermal conductivity kunokubonwa kwi-substrate yezixhobo ze-semiconductor, izinto ze-ceramic conductivity eziphezulu ze-thermal conductivity, izifudumezi kunye neepleyiti zokufudumeza zokusetyenzwa kwe-semiconductor, izinto ze-capsule zamafutha enyukliya, kunye namakhonkco okutywinwa kwegesi kwiimpompo ze-compressor.
Ukusetyenziswa kwei-silicon carbidekwintsimi ye-semiconductor
Iidiski zokusila kunye nokulungiswa zizixhobo ezibalulekileyo zenkqubo yokuvelisa i-silicon wafer kushishino lwe-semiconductor. Ukuba i-disc yokugaya yenziwe ngentsimbi okanye i-carbon steel, ubomi bayo benkonzo bufutshane kwaye i-coefficient yayo yokwandisa i-thermal inkulu. Ngexesha lokucutshungulwa kwee-silicone wafers, ngakumbi ngexesha lokusila okanye ukupolisha ngesantya esiphezulu, ngenxa yokunxiba kunye ne-thermal deformation yediski yokusila, i-flatness kunye ne-parallelism ye-silicon wafer kunzima ukuqinisekisa. Idiskhi yokusila eyenziwei-silicon carbide ceramicsinokugqoka okuphantsi ngenxa yokuqina kwayo okuphezulu, kwaye i-coefficient yayo yokwandisa i-thermal ifana ngokusisiseko naleyo ye-silicon wafers, ngoko inokugutywa kwaye ipoliswe ngesantya esiphezulu.
Ukongeza, xa ii-wafers ze-silicon ziveliswa, kufuneka zingene kunyango lobushushu obuphezulu kwaye zihlala zithuthwa kusetyenziswa izixhobo ze-silicon carbide. Ziyakwazi ukumelana nobushushu kwaye zingonakalisi. Ikhabhoni efana nedayimane (i-DLC) kunye nezinye iingubo zokwaleka zingafakwa kumphezulu wokuphucula ukusebenza, ukunciphisa umonakalo owenziwe nge-wafer, kunye nokuthintela ukosuleleka ekusasazekeni.
Ngapha koko, njengommeli wesizukulwana sesithathu esibanzi-bandgap semiconductor materials, isilicon carbide single crystal imathiriyeli ineepropathi ezifana ne-bandgap enkulu yobubanzi (malunga namaxesha ama-3 eSi), i-thermal conductivity ephezulu (malunga ne-3.3 amaxesha e-Si okanye amaxesha e-10 leyo ye-GaAs), izinga eliphezulu lokufuduka kwe-electron (malunga ne-2.5 amaxesha e-Si) kunye nentsimi yombane ephukileyo (malunga Amaxesha e-10 awe-Si okanye ama-5 amaxesha e-GaAs). Izixhobo ze-SiC zenza iziphene zezixhobo zemveli ze-semiconductor kwizicelo eziphathekayo kwaye ngokuthe ngcembe ziba yinto ephambili ye-semiconductors yamandla.
Imfuno ye-thermal conductivity ephezulu ye-silicon carbide ceramics inyuke kakhulu
Ngophuhliso oluqhubekayo lwesayensi kunye nethekhnoloji, imfuno yokusetyenziswa kwe-silicon carbide ceramics kwintsimi ye-semiconductor iye yanda kakhulu, kwaye i-thermal conductivity ephezulu isalathiso esibalulekileyo sokusetyenziswa kwayo kumacandelo ezixhobo zokuvelisa i-semiconductor. Ke ngoko, kubalulekile ukomeleza uphando kwi-thermal conductivity ye-silicon carbide ceramics. Ukunciphisa umxholo we-oksijini we-lattice, ukuphucula ukuxinana, kunye nokulawula ngokufanelekileyo ukuhanjiswa kwesigaba sesibini kwi-lattice yizona ndlela eziphambili zokuphucula ukuhanjiswa kwe-thermal ye-silicon carbide ceramics.
Okwangoku, kukho izifundo ezimbalwa kwi-thermal conductivity silicon carbide ceramics kwilizwe lam, kwaye kusekho umsantsa omkhulu xa kuthelekiswa nenqanaba lehlabathi. Izalathiso zophando lwexesha elizayo ziquka:
● Yomeleza inkqubo yokulungiselela uphando lwe-silicon carbide ceramic powder. Ukulungiswa kwe-high-purity, i-oksijini ephantsi ye-silicon carbide powder sisiseko sokulungiswa kwe-thermal conductivity ye-silicon carbide ceramics;
● Ukomeleza ukhetho lwezixhobo zokuncedisa ukufunda nophando olunxulumene nethiyori;
●Qinisa uphando kunye nophuhliso lwezixhobo eziphezulu ze-sintering. Ngokulawula inkqubo ye-sintering ukufumana i-microstructure efanelekileyo, yimeko efunekayo ukufumana i-thermal conductivity ye-silicon carbide ceramics.
Amanyathelo okuphucula i-thermal conductivity ye-silicon carbide ceramics
Isitshixo sokuphucula i-thermal conductivity ye-SiC ceramics kukunciphisa i-phonon scattering frequency kunye nokwandisa i-phonon ithetha indlela yamahhala. I-thermal conductivity ye-SiC iya kuphuculwa ngokufanelekileyo ngokunciphisa i-porosity kunye ne-grain boundary density ye-Ceramics ye-SiC, ukuphucula ukucoceka kwemida yeenkozo ze-SiC, ukunciphisa ukungcola kwe-SiC lattice okanye i-lattice defects, kunye nokwandisa umthuthi wokuhamba kobushushu kwi-SiC. Okwangoku, ukulungelelanisa uhlobo kunye nomxholo wezixhobo zokuncedisa kunye nokushisa ukushisa okuphezulu yimilinganiselo ephambili yokuphucula i-thermal conductivity ye-ceramics ye-SiC.
① Ukuphucula uhlobo kunye nomxholo wezixhobo zokuncedisa
Iintlobo ezahlukeneyo zokuncedisa i-sintering zihlala zongezwa xa kulungiswa i-thermal conductivity ye-SiC ceramics. Phakathi kwabo, uhlobo kunye nomxholo we-sintering aids inempembelelo enkulu kwi-thermal conductivity ye-ceramics ye-SiC. Ngokomzekelo, izinto ze-Al okanye i-O kwi-Al2O3 ye-sintering aid zichithwa ngokulula kwi-lattice ye-SiC, okubangela izithuba kunye neziphene, ezikhokelela ekwandeni kwe-phonon yokusabalalisa i-frequency. Ukongezelela, ukuba umxholo we-sintering aids uphantsi, izinto eziphathekayo zinzima ukuhlambalaza kunye nokunciphisa, ngelixa umxholo ophezulu we-sintering aids uya kubangela ukwanda kokungcola kunye neziphene. Uncedo olugqithisiweyo lwesigaba solwelo lwe-sintering lunokuthintela ukukhula kweenkozo ze-SiC kunye nokunciphisa indlela yasimahla yeephononi. Ngoko ke, ukuze kulungiswe i-thermal conductivity ye-SiC ceramics, kuyimfuneko ukunciphisa umxholo we-sintering aids kangangoko kunokwenzeka ngelixa uhlangabezana neemfuno ze-sintering density, kwaye uzame ukukhetha izixhobo zokuncedisa ekunzima ukunyibilika kwi-lattice ye-SiC.
*Iipropathi ezishushu ze-SiC Ceramics xa i-sintering aid ezahlukeneyo zongezwa
Okwangoku, ii-ceramics ze-SiC eziciniweyo ezishushu ezifakwe kwi-BeO njenge-sintering aid zineqondo eliphezulu lobushushu obuphezulu begumbi (270W · m-1 · K-1). Nangona kunjalo, i-BeO yinto enetyhefu kakhulu kunye ne-carcinogenic, kwaye ayifanelekanga ukusetyenziswa ngokubanzi kwiilabhoratri okanye kwiindawo zoshishino. Indawo esezantsi ye-eutectic yenkqubo ye-Y2O3-Al2O3 yi-1760 ℃, eyona nto ixhaphakileyo ye-liquid-phase sintering aid kwii-ceramics ze-SiC. Nangona kunjalo, ekubeni i-Al3 + ichithwa ngokulula kwi-lattice ye-SiC, xa le nkqubo isetyenziswa njenge-sintering aid, i-conductivity ye-thermal yegumbi ye-SiC ceramics ingaphantsi kwe-200W · m-1 · K-1.
Izinto ezinqabileyo zomhlaba ezifana ne-Y, Sm, Sc, Gd kunye ne-La azinakunyibilika ngokulula kwi-lattice ye-SiC kwaye zine-oksijini ephezulu, enokunciphisa ngokufanelekileyo umxholo we-oksijini we-SiC lattice. Ngoko ke, inkqubo ye-Y2O3-RE2O3 (RE=Sm, Sc, Gd, La) yinto eqhelekileyo yokuncedisa ekulungiseleleni ukuhanjiswa kwe-thermal ephezulu (> 200W · m-1 · K-1) ii-ceramics ze-SiC. Ukuthatha i-Y2O3-Sc2O3 inkqubo yokuncedisa i-sintering aid njengomzekelo, ixabiso le-ion lokuphambuka kwe-Y3 + kunye ne-Si4 + likhulu, kwaye ezimbini azifumani isisombululo esiqinileyo. I-solubility ye-Sc kwi-SiC ecocekileyo kwi-1800 ~ 2600℃ incinci, malunga (2~3) × 1017atoms · cm-3.
② Unyango lobushushu obuphezulu
Ukuphathwa kobushushu obuphezulu be-SiC ceramics kukulungele ukuphelisa iziphene ze-lattice, ukuchithwa kunye noxinzelelo olushiyekileyo, ukukhuthaza ukuguqulwa kwesakhiwo sezinto ezithile ze-amorphous kwiikristale, kunye nokunciphisa i-phonon scattering effect. Ukongezelela, unyango olushushu oluphezulu lunokukhuthaza ngokufanelekileyo ukukhula kweenkozo ze-SiC, kwaye ekugqibeleni kuphuculwe iimpawu ze-thermal eziphathekayo. Ngokomzekelo, emva kokunyangwa kobushushu obuphezulu kwi-1950 ° C, i-coefficient ye-thermal diffusion ye-ceramics ye-SiC yanda ukusuka kwi-83.03mm2 · s-1 ukuya kwi-89.50mm2 · s-1, kwaye i-conductivity ye-thermal yegumbi inyuke ukusuka kwi-180.94W · m. -1·K-1 ukuya ku-192.17W · m-1 · K-1. Ubushushu obuphezulu bobushushu bonyango buphucula ngempumelelo isakhono se-deoxidation soncedo lokuthambisa kumphezulu weSiC kunye nelatisi, kwaye lwenza udibaniso phakathi kweenkozo zeSiC lube lukhuni. Emva konyango lobushushu obuphezulu, i-thermal conductivity yegumbi le-SiC ceramics iphuculwe kakhulu.
Ixesha lokuposa: Oct-24-2024