Ubunzima bobugcisa ekuveliseni ubunzima obuzinzileyo obuphezulu be-silicon carbide wafers kunye nokusebenza okuzinzileyo kubandakanya:
1) Ekubeni iikristali kufuneka zikhule kwindawo yokushisa evaliweyo ngaphezu kwe-2000 ° C, iimfuno zokulawula ubushushu ziphezulu kakhulu;
2) Ekubeni i-silicon carbide inezakhiwo zekristale ezingaphezu kwama-200, kodwa kuphela izakhiwo ezimbalwa ze-crystal silicon carbide eziyimfuneko ye-semiconductor, i-silicon-to-carbon ratio, i-gradient yokukhula, kunye nokukhula kwekristale kufuneka kulawulwe ngokuchanekileyo ngexesha. inkqubo yokukhula kwekristale. Iiparamitha ezifana nesantya kunye noxinzelelo lokuhamba komoya;
3) Ngaphantsi kwendlela yokuhanjiswa kwesigaba somphunga, iteknoloji yokwandisa ububanzi be-silicon carbide crystal ukukhula kunzima kakhulu;
I-4) Ukuqina kwe-silicon carbide kusondele kwidayimane, kwaye ukusika, ukucola, kunye neendlela zokupolisha kunzima.
I-SiC epitaxial wafers: idla ngokuveliswa yindlela yokubeka umphunga wekhemikhali (CVD). Ngokweentlobo ezahlukeneyo ze-doping, zahlulwe zibe yi-n-type kunye ne-p-type epitaxial wafers. I-Domestic Hantian Tiancheng kunye ne-Dongguan Tianyu ingaba sele ibonelele nge-4-intshi/6-intshi ye-SiC epitaxial wafers. Kwi-epitaxy ye-SiC, kunzima ukulawula kwintsimi ye-voltage ephezulu, kwaye umgangatho we-SiC epitaxy unempembelelo enkulu kwizixhobo ze-SiC. Ngaphezu koko, izixhobo ze-epitaxial zilawulwa ziinkampani ezine eziphambili kwishishini: i-Axitron, i-LPE, i-TEL kunye ne-Nuflare.
I-silicon carbide epitaxialI-wafer ibhekisa kwi-silicon carbide wafer apho ifilimu yekristale enye (i-epitaxial layer) eneemfuno ezithile kunye ne-substrate crystal ikhuliswe kwi-silicon carbide substrate yokuqala. Ukukhula kwe-Epitaxial ikakhulu kusebenzisa i-CVD (i-Chemical Vapor Deposition, ) izixhobo okanye i-MBE (i-Molecular Beam Epitaxy) izixhobo. Ekubeni izixhobo ze-silicon carbide zenziwe ngokuthe ngqo kwi-epitaxial layer, umgangatho we-epitaxial layer uchaphazela ngokuthe ngqo ukusebenza kunye nesivuno sesixhobo. Njengoko i-voltage ukumelana nokusebenza kwesixhobo iqhubeka ikhula, ubukhulu be-epitaxial layer ehambelanayo buba bukhulu kwaye ulawulo luba nzima. Ngokuqhelekileyo, xa i-voltage ijikeleze i-600V, ubukhulu obufunekayo be-epitaxial layer malunga ne-6 microns; xa i-voltage iphakathi kwe-1200-1700V, ubukhulu obufunekayo be-epitaxial layer bufikelela kwi-10-15 microns. Ukuba i-voltage ifikelela ngaphezu kwe-10,000 volts, ubuninzi be-epitaxial layer ngaphezu kwe-100 microns bunokufuneka. Njengoko ubukhulu bomaleko we-epitaxial buqhubeka bukhula, kuya kuba nzima ngakumbi ukulawula ukutyeba kunye nokulingana kokumelana kunye nokuxinana kwesiphene.
Izixhobo ze-SiC: Kumazwe ngamazwe, i-600 ~ 1700V SiC SBD kunye ne-MOSFET ziye zaphuhliswa. Iimveliso eziphambili zisebenza kumanqanaba ombane angaphantsi kwe-1200V kwaye ngokuyintloko zamkele ukupakishwa kwe-TO. Ngokubhekiselele kumaxabiso, iimveliso ze-SiC kwimarike yamazwe ngamazwe zixabisa malunga namaxesha angama-5-6 aphezulu kunoogxa babo beSi. Nangona kunjalo, amaxabiso ayehla ngesantya sonyaka se-10%. kunye nokwandiswa kwezinto eziphezulu kunye nokuveliswa kwesixhobo kwiminyaka eyi-2-3 ezayo, ukunikezelwa kweemarike kuya kunyuka, okukhokelela ekunciphiseni okungakumbi. Kulindeleke ukuba xa ixabiso lifikelela ku-2-3 amaxesha eemveliso ze-Si, izibonelelo eziziswa kukunciphisa iindleko zenkqubo kunye nokusebenza okuphuculweyo kuya kuqhuba ngokuthe ngcembe i-SiC ukuba ithathe indawo yemarike yezixhobo zeSi.
Ukupakishwa kwemveli kusekelwe kwi-silicon-based substrates, ngelixa izixhobo ze-semiconductor zesizukulwana sesithathu zifuna uyilo olutsha ngokupheleleyo. Ukusebenzisa izakhiwo zokupakisha ezisekelwe kwi-silicon yezixhobo zamandla ezibanzi-bandgap kunokwazisa imiba emitsha kunye nemingeni enxulumene nokuphindaphinda, ulawulo lobushushu kunye nokuthembeka. Izixhobo zamandla e-SiC zinovakalelo ngakumbi kwi-parasitic capacitance kunye ne-inductance. Xa kuthelekiswa nezixhobo ze-Si, iitshiphusi zamandla zeSiC zinesantya sokutshintsha ngokukhawuleza, nto leyo inokukhokelela ekudubuleni, i-oscillation, ilahleko eyandisiweyo yokutshintsha, kunye nokungasebenzi kakuhle kwesixhobo. Ukongeza, izixhobo zamandla e-SiC zisebenza kumaqondo obushushu aphezulu, zifuna iindlela zolawulo oluphezulu lobushushu.
Iindidi ezahlukeneyo zezakhiwo ziye zaphuhliswa kwibala le-wide-bandgap semiconductor power packaging. Ukupakishwa kwemodyuli yamandla e-Si yemveli ayisafanelekanga. Ukuze kulungiswe iingxaki zeeparameters eziphezulu zeparasitic kunye nokusebenza kakubi kokutshatyalaliswa kobushushu bemveli yokupakisha imodyuli yamandla e-Si, ukupakishwa kwemodyuli yamandla e-SiC kwamkela uqhagamshelwano olungenacingo kunye neteknoloji yokupholisa kabini kwisakhiwo sayo, kwaye yamkele izixhobo ze-substrate nge-thermal engcono. conductivity, kwaye wazama ukudibanisa i-capacitors edibeneyo, iqondo lokushisa / i-sensor zangoku, kunye nokuqhuba iisekethe kwimodyuli yesakhiwo, kunye nokuphuhlisa ukupakishwa kweemodyuli ezahlukeneyo. ubugcisa. Ngaphezu koko, kukho imiqobo ephezulu yobugcisa kwimveliso yesixhobo se-SiC kunye neendleko zemveliso ziphezulu.
Izixhobo ze-silicon carbide ziveliswa ngokubeka i-epitaxial layers kwi-silicon carbide substrate nge-CVD. Inkqubo ibandakanya ukucoca, i-oxidation, i-photolithography, i-etching, ukuhluthwa kwe-photoresist, ukufakwa kwe-ion, ukufakwa komphunga wekhemikhali ye-silicon nitride, ukupolisha, ukutshiza, kunye namanyathelo okucubungula alandelayo ukwenza isakhiwo sesixhobo kwi-SiC enye ye-crystal substrate. Iindidi eziphambili zezixhobo zamandla ze-SiC ziquka ii-diode ze-SiC, ii-transistors ze-SiC, kunye neemodyuli zamandla ze-SiC. Ngenxa yezinto ezifana nokucotha kwesantya sokuvelisa izinto kunye namazinga asezantsi esivuno, izixhobo ze-silicon carbide zineendleko eziphezulu zokwenziwa.
Ukongeza, ukuveliswa kwesixhobo se-silicon carbide kunobunzima obuthile bobugcisa:
1) Kuyimfuneko ukuphuhlisa inkqubo ethile ehambelana neempawu ze-silicon carbide materials. Umzekelo: I-SiC inendawo ephezulu yokunyibilika, nto leyo eyenza ukuba ukusasazwa kwe-thermal kungasebenzi. Kuyimfuneko ukusebenzisa i-ion implantation doping method kunye nokulawula ngokuchanekileyo iiparameters ezifana neqondo lobushushu, izinga lokufudumeza, ixesha, kunye nokuhamba kwegesi; I-SiC ayisebenzi kwizinyibilikisi zemichiza. Kufuneka kusetyenziswe iindlela ezinjengokomisa okomileyo, kunye nezixhobo zemaski, imixube yerhasi, ulawulo lwethambeka elisecaleni, izinga lokurhabula, uburhabaxa becala, njl. njl. kufuneka luphuculwe kwaye luphuhliswe;
I-2) Ukwenziwa kwee-electrode zetsimbi kwi-silicon carbide wafers kufuna ukuchasana noqhagamshelwano ngaphantsi kwe-10-5Ω2. Izinto ze-electrode ezihlangabezana neemfuno, i-Ni kunye ne-Al, zinozinzo olubi lwe-thermal ngaphezu kwe-100 ° C, kodwa i-Al / Ni inozinzo olungcono lwe-thermal. Ukuchasana okuthe ngqo koqhagamshelwano lwe-/W/Au yezinto ezidibeneyo ze-electrode yi-10-3Ω2 ephezulu;
I-3) I-SiC ineengubo eziphezulu zokusika, kwaye ubunzima be-SiC bungokwesibini kuphela kwidayimane, ebeka phambili iimfuno eziphezulu zokusika, ukugawula, ukupolisha kunye nobunye ubuchwepheshe.
Ngaphezu koko, izixhobo zamandla e-silicon carbide ze-trench zinzima kakhulu ukwenza. Ngokwezakhiwo zesixhobo ezahlukeneyo, izixhobo zamandla e-silicon carbide zinokuhlulwa ikakhulu zibe zizixhobo ezicwangcisiweyo kunye nezixhobo zomsele. Izixhobo zamandla e-Planar silicon carbide zineyunithi engaguqukiyo kunye nenkqubo elula yokuvelisa, kodwa zityekele kwisiphumo se-JFET kwaye zinamandla aphezulu e-parasitic kunye nokumelana nombuso. Xa kuthelekiswa nezixhobo ezicwangcisiweyo, izixhobo zamandla ze-silicon carbide ze-trench zineyunithi engaguqukiyo kwaye zinenkqubo yokuvelisa enzima ngakumbi. Nangona kunjalo, ubume bomsele buluncedo ekwandiseni ukuxinana kweyunithi yesixhobo kwaye akunakufane kwenzeke ukuvelisa isiphumo se-JFET, esiluncedo ekusombululeni ingxaki yokushukumiseka kwetshaneli. Ineepropathi ezigqwesileyo ezifana nokunganyangeki, i-parasitic capacitance encinci, kunye nokutshintsha okuphantsi kokusetyenziswa kwamandla. Ineendleko ezibalulekileyo kunye neenzuzo zokusebenza kwaye iye yaba ngumkhombandlela ophambili wophuhliso lwezixhobo zamandla ze-silicon carbide. Ngokutsho kwe-website ye-Rohm esemthethweni, isakhiwo se-ROHM Gen3 (isakhiwo se-Gen1 Trench) kuphela i-75% yendawo ye-chip ye-Gen2 (i-Plannar2), kunye ne-ROHM Gen3 yokumelana nokumelana nokunciphisa i-50% phantsi kobukhulu obufanayo be-chip.
I-Silicon carbide substrate, i-epitaxy, i-front-end, iindleko ze-R & D kunye nezinye i-akhawunti ye-47%, i-23%, i-19%, i-6% kunye ne-5% yeendleko zokwenziwa kwezixhobo ze-silicon carbide ngokulandelanayo.
Ekugqibeleni, siya kugxila ekwaphuleni izithintelo zobugcisa ze-substrates kwi-silicon carbide industry chain.
Inkqubo yokuvelisa i-silicon carbide substrates iyafana naleyo ye-silicon-based substrates, kodwa inzima ngakumbi.
Inkqubo yokwenziwa kwe-silicon carbide substrate ngokubanzi ibandakanya ukuhlanganiswa kwemathiriyeli ekrwada, ukukhula kwekristale, ukusetyenzwa kwe-ingot, ukusika i-ingot, ukugaya i-wafer, ukupolisha, ukucocwa kunye namanye amakhonkco.
Inqanaba lokukhula kwekristale lisisiseko senkqubo yonke, kwaye eli nyathelo limisela iimpawu zombane ze-silicon carbide substrate.
Izinto ze-silicon carbide zinzima ukukhula kwisigaba samanzi phantsi kweemeko eziqhelekileyo. Indlela yokukhula kwesigaba somphunga ethandwa kwimarike namhlanje inobushushu obungaphezulu kwe-2300°C kwaye ifuna ulawulo oluchanekileyo lobushushu bokukhula. Yonke le nkqubo yokusebenza iphantse yanzima ukuyiqwalasela. Impazamo encinci iya kukhokelela ekukhutshweni kwemveliso. Xa kuthelekiswa, izinto ze-silicon zifuna kuphela i-1600 ℃, ephantsi kakhulu. Ukulungiselela i-silicon carbide substrates ikwajongene nobunzima obufana nokukhula okucothayo kwekristale kunye neemfuno eziphezulu zeekristale. Ukukhula kweSilicon carbide wafer kuthatha malunga ne-7 ukuya kwiintsuku ze-10, ngelixa ukutsala intonga ye-silicon kuthatha kuphela iintsuku ezi-2 ezinesiqingatha. Ngaphezu koko, i-silicon carbide yinto enobunzima obukwisibini kuphela kwidayimane. Kuya kulahlekelwa kakhulu ngexesha lokusika, ukugawula, kunye nokupholisha, kwaye umlinganiselo wokuphuma ngu-60% kuphela.
Siyazi ukuba umkhwa kukunyusa ubungakanani be-silicon carbide substrates, njengoko ubungakanani buqhubeka bukhula, iimfuno zetekhnoloji yokwandisa ububanzi ziba phezulu kwaye ziphezulu. Ifuna indibaniselwano yezinto ezahlukeneyo zolawulo lobugcisa ukufezekisa ukukhula okuphindaphindiweyo kweekristale.
Ixesha lokuposa: May-22-2024