Yintoni isithando sokukhulisa ikristale sesilicon carbide (SiC)?

I-SiCineempawu ze-bandgap enkulu, ukuqhuba okuphezulu kobushushu, amandla entsimi yokuqhekeka okubalulekileyo okuphezulu, kunye nesantya esiphezulu sokutyibilika kwe-electron saturation. Ingahlangabezana neemfuno zesicelo phantsi kobushushu obuphezulu, uxinzelelo oluphezulu, i-frequency ephezulu, kunye neemeko zamandla aphezulu. Ingasetyenziswa kakhulu kwizithuthi zamandla amatsha, ii-photovoltaics, ulawulo lwemizi-mveliso, unxibelelwano lwerediyo kunye nezinye iindawo. Ngophuhliso olukhawulezayo lwamashishini anxulumene noko, imakethi ye-semiconductor yesizukulwana sesithathu emelwe yi-silicon carbide ingenise amathuba amatsha.

Ukukhula kwekristale yeyona khonkco iphambili yemveliso ye-silicon carbide substrate, kwaye izixhobo eziphambili sisithando sokukhulisa ikristale. Njengezithando zemveli zokukhulisa ikristale ze-silicon-grade, isakhiwo sesithando asinzima kakhulu. Siqulathe umzimba wesithando, inkqubo yokufudumeza, indlela yokudlulisa i-coil, inkqubo yokufumana i-vacuum kunye nokulinganisa, inkqubo yendlela yegesi, inkqubo yokupholisa, inkqubo yolawulo, njl. Intsimi yobushushu kunye neemeko zenkqubo zimisela izalathisi eziphambili zomgangatho wekristale ye-silicon carbide, ubungakanani, ukuqhuba kunye nezinye izalathisi eziphambili.

Ⅰ. Ubunzima kwiteknoloji yokukhula kwekristale yesilicon carbide

Ubushushu bokukhula kwekristale ye-silicon carbide buphezulu kakhulu kwaye abunakubekwa esweni, ngoko ke ubunzima obuphambili bukwinkqubo ngokwayo:

(1)Ubunzima bokulawula intsimi yobushushu: Ukubekwa esweni komngxuma ovaliweyo wobushushu obuphezulu kunzima kwaye akunakulawuleka. Ngokungafaniyo nezixhobo zokukhulisa ikristale ezisekelwe kwisisombululo esitsalwa yisilicon, ezinezinga eliphezulu lokuzenzekela kwaye inkqubo yokukhula kwekristale inokubonwa, ilawulwe kwaye ilungiswe, iikristale ze-silicon carbide zikhula kwindawo evaliweyo kwindawo enobushushu obuphezulu ngaphezu kwe-2,000°C, kwaye ubushushu bokukhula kufuneka bulawulwe ngokuchanekileyo ngexesha lokuveliswa, okwenza kube nzima ukulawula ubushushu;

(2)Ubunzima bokulawula imo yekristale: IiMicropipes, i-polymorphic inclusions, i-dislocations kunye nezinye iziphene zinokwenzeka ngexesha lenkqubo yokukhula, kwaye ziyachaphazela kwaye ziguqukele kwenye nenye. IiMicropipes (MP) ziziphene ezisebenzisa uhlobo oluhambayo ezinobukhulu obuziimicrons ezininzi ukuya kwi-ten microns, eziziiphene ezibulalayo kwizixhobo. Iikristale zeSilicon carbide enye ziquka iintlobo zekristale ezahlukeneyo ezingaphezu kwama-200, kodwa zimbalwa izakhiwo zekristale (Uhlobo lwe-4H) zezona zinto ze-semiconductor ezifunekayo kwimveliso. Utshintsho kwimo yekristale lunokwenzeka ngexesha lenkqubo yokukhula, nto leyo ekhokelela kwiziphene zokubandakanywa kwe-polymorphic. Ke ngoko, kuyimfuneko ukulawula ngokuchanekileyo iiparameter ezifana nomlinganiselo we-silicon-carbon, i-gradient yobushushu bokukhula, isantya sokukhula kwekristale, kunye noxinzelelo lokuhamba kwegesi.

Ukongeza, kukho i-gradient yobushushu kwintsimi yobushushu yokukhula kwe-silicon carbide single crystal, ekhokelela kuxinzelelo lwangaphakathi lwendalo kunye nokuphuma okubangelwa kukusuka kwe-basal plane dislocation (i-basal plane dislocation BPD, i-screw dislocation TSD, i-edge dislocation TED) ngexesha lenkqubo yokukhula kwe-crystal, ngaloo ndlela ichaphazela umgangatho kunye nokusebenza kwe-epitaxy elandelayo kunye nezixhobo.

(3)Ulawulo olunzima lokusebenzisa iziyobisi: Ukungeniswa kokungcola kwangaphandle kufuneka kulawulwe ngokungqongqo ukuze kufunyanwe ikristale eqhubayo ene-doping eqondisayo;

(4)Izinga lokukhula elicothayo: Izinga lokukhula kwe-silicon carbide licotha kakhulu. Yemveliizixhobo zesiliconkufuneka iintsuku ezi-3 kuphela ukuze ikhule ibe yi-crystal rod, ngelixa ii-silicon carbide crystal rods zifuna iintsuku ezi-7. Oku kukhokelela ekubeni imveliso ye-silicon carbide ibe phantsi ngokwendalo kwaye imveliso yayo incinci kakhulu.

Kwelinye icala, iiparameter zokukhula kwe-silicon carbide epitaxial zifuna kakhulu, kubandakanya ukungabi namoya kwezixhobo, ukuzinza koxinzelelo lwegesi kwigumbi lokusabela, ulawulo oluchanekileyo lwexesha lokungeniswa kwegesi, ukuchaneka komlinganiselo wegesi, kunye nolawulo olungqongqo lobushushu bokubekwa. Ngokukodwa, ngokuphuculwa kwenqanaba le-voltage yokumelana nesixhobo, ubunzima bokulawula iiparameter eziphambili ze-epitaxial wafer bunyuke kakhulu.

Ukongeza, ngokonyuka kobukhulu beleya ye-epitaxial, indlela yokulawula ukufana kokumelana nokunciphisa uxinano lwesiphako ngelixa kuqinisekiswa ukuba ubukhulu bube ngomnye umceli mngeni omkhulu. Kwinkqubo yolawulo olusebenzisa umbane, kuyimfuneko ukudibanisa ii-sensors kunye nee-actuators ezichanekileyo ukuqinisekisa ukuba iiparameter ezahlukeneyo zinokulawulwa ngokuchanekileyo nangokuzinzileyo. Kwangaxeshanye, ukulungiswa kwe-algorithm yokulawula nako kubalulekile. Kufuneka ikwazi ukulungisa icebo lokulawula ngexesha langempela ngokwesignali yempendulo ukuze ivumelane notshintsho oluhlukeneyo kwiukukhula kwe-epitaxial ye-silicon carbideinkqubo.

Ⅱ. Ubunzima obuphambili ekuvelisweni kwe-silicon carbide substrates:

1. Ubushushu bokukhula bungaphezulu kwama-2000℃, obuphindwe kabini kunobo be-silicon.

2. Ubukhulu bentonga yekristale buncinci ngexesha lokukhula kwekristale, kwaye intonga yekristale yesilicon carbide eyi-2cm ikhula kwiintsuku ezisi-7.

3. Iimfuno zohlobo lwekristale ziphezulu, kwaye kukho i-silicon carbide encinci yekristale enye enezakhiwo zekristale.

4. Ukusika kuphezulu kakhulu, kwaye i-silicon carbide inobunzima obuphezulu kakhulu.

Ngamafutshane, iindleko zexesha ezibizayo kunye netekhnoloji yokucubungula enzima zigqiba ixabiso eliphezulu le-silicon carbide substrates, nto leyo ethintela ukusetyenziswa kwe-silicon carbide.

III. Ukwahlulwahlulwa kwee-furnace zokukhula kwekristale

Ngokweendlela ezahlukeneyo zokufudumeza, izithando zokukhulisa ikristale zinokwahlulwa zibe luhlobo lokungenisa kunye nohlobo lokumelana. Okwangoku, uninzi lwezixhobo ezikwimarike luhlobo lokungenisa, olunezibonelelo zexabiso eliphantsi, isakhiwo esilula, ukugcinwa okulula kunye nokusebenza kakuhle kobushushu. Nangona kunjalo, ngenxa yesiphumo sokungenisa i-electromagnetic, ubushushu be-axial kunye nobushushu be-radial bokufudumala kwe-induction zidityanisiwe, kwaye akunakwenzeka ukuba kuthathelwe ingqalelo isantya sokukhula kwekristale kunye nomgangatho wokukhula kwekristale.

Iqonga lokukhula kwentsimi yobushushu elichaseneyo linokulawula ngokuchanekileyo ubushushu be-axial kunye nobushushu be-radial ngokulandelelana, nto leyo ekhuthaza ukukhula kweekristale ezinkulu kwaye iphucule izinga lokukhula kwekristale. Sesinye sezisombululo zokukhula kwekristale ye-silicon carbide ekumgangatho ophezulu ye-8-intshi kwixesha elizayo.

Uthelekiso phakathi kwendlela yokungenisa kunye nendlela yokumelana: