Ubunzima bobuchwepheshe kuma-wafer e-silicon carbide akhiqiza ngobuningi obuzinzile futhi asebenza kahle buhlanganisa:
1) Njengoba amakristalu edinga ukukhula endaweni evalwe ngezinga lokushisa eliphezulu ngaphezu kuka-2000°C, izidingo zokulawula izinga lokushisa ziphakeme kakhulu;
2) Njengoba i-silicon carbide inezakhiwo zekristalu ezingaphezu kuka-200, kodwa zimbalwa kuphela izakhiwo ze-single-crystal silicon carbide eziyizinto ezidingekayo ze-semiconductor, isilinganiso se-silicon-to-carbon, i-gradient yokushisa kokukhula, kanye nokukhula kwekristalu kudingeka kulawulwe ngokunembile ngesikhathi senqubo yokukhula kwekristalu. Amapharamitha anjengejubane kanye nomfutho wokugeleza komoya;
3) Ngaphansi kwendlela yokudlulisa isigaba somusi, ubuchwepheshe bokukhulisa ububanzi bokukhula kwekristalu ye-silicon carbide bunzima kakhulu;
4) Ubulukhuni be-silicon carbide bufana nobedayimane, futhi amasu okusika, ukugaya, nokupholisha anzima.
Ama-wafer e-SiC epitaxial: avame ukukhiqizwa ngendlela ye-chemical vapor deposition (CVD). Ngokwezinhlobo ezahlukene ze-doping, ahlukaniswe ngama-wafer e-epitaxial epitaxial e-n-type kanye nama-wafer e-p-type. I-Domestic Hantian Tiancheng kanye ne-Dongguan Tianyu kakade zingahlinzeka ngama-wafer e-SiC epitaxial epitaxial e-4-inch/6-inch. Ku-SiC epitaxy, kunzima ukuyilawula ensimini ye-high-voltage, futhi ikhwalithi ye-SiC epitaxy inomthelela omkhulu kumadivayisi e-SiC. Ngaphezu kwalokho, imishini ye-epitaxial ilawulwa yizinkampani ezine ezihamba phambili embonini: i-Axitron, i-LPE, i-TEL kanye ne-Nuflare.
I-epitaxial ye-silicon carbideI-wafer ibhekisela ku-wafer ye-silicon carbide lapho kukhuliswa khona ifilimu eyodwa yekristalu (ungqimba lwe-epitaxial) enezidingo ezithile futhi efana nekristalu ye-substrate ku-substrate yokuqala ye-silicon carbide. Ukukhula kwe-Epitaxial kusebenzisa kakhulu imishini ye-CVD (Chemical Vapor Deposition, ) noma imishini ye-MBE (Molecular Beam Epitaxy). Njengoba amadivayisi e-silicon carbide ekhiqizwa ngqo kungqimba lwe-epitaxial, ikhwalithi yengqimba ye-epitaxial ithinta ngqo ukusebenza kanye nokukhiqiza kwedivayisi. Njengoba i-voltage imelana nokusebenza kwedivayisi iqhubeka nokukhula, ukujiya kwengqimba ye-epitaxial ehambisanayo kuba mkhulu futhi ukulawula kuba nzima kakhulu. Ngokuvamile, lapho i-voltage icishe ibe ngu-600V, ukujiya kwengqimba ye-epitaxial edingekayo kungaba cishe ama-microns ayi-6; lapho i-voltage iphakathi kuka-1200-1700V, ukujiya kwengqimba ye-epitaxial edingekayo kufinyelela kuma-microns ayi-10-15. Uma i-voltage ifinyelela ngaphezu kwama-volts ayi-10,000, kungadingeka ukujiya kwengqimba ye-epitaxial engaphezu kwama-microns ayi-100. Njengoba ukujiya kwengqimba ye-epitaxial kuqhubeka nokwanda, kuba nzima kakhulu ukulawula ukujiya kanye nokuphikiswa okufanayo kanye nobuningi beziphambeko.
Amadivayisi e-SiC: Emhlabeni jikelele, i-SiC SBD engu-600 ~ 1700V kanye ne-MOSFET sezithuthukisiwe. Imikhiqizo eyinhloko isebenza emazingeni e-voltage angaphansi kuka-1200V futhi ikakhulukazi isebenzisa ukupakishwa kwe-TO. Ngokuphathelene namanani, imikhiqizo ye-SiC emakethe yamazwe ngamazwe inentengo ephakeme cishe ngokuphindwe ka-5-6 kunezakwabo ze-Si. Kodwa-ke, amanani ehla ngesilinganiso sonyaka esingu-10%. ngokwandiswa kwezinto zokwakha ezisezingeni eliphezulu kanye nokukhiqizwa kwamadivayisi eminyakeni engu-2-3 ezayo, ukunikezwa kwemakethe kuzokwanda, okuholela ekwehleni kwentengo okuqhubekayo. Kulindeleke ukuthi lapho intengo ifinyelela izikhathi eziphindwe ka-2-3 kunemikhiqizo ye-Si, izinzuzo ezilethwa izindleko zesistimu ezincishisiwe kanye nokusebenza okuthuthukisiwe kuzoqhuba i-SiC kancane kancane ukuthi ithathe indawo yemakethe yamadivayisi e-Si.
Ukupakishwa kwendabuko kusekelwe kuma-substrate asekelwe ku-silicon, kuyilapho izinto ze-semiconductor zesizukulwane sesithathu zidinga umklamo omusha ngokuphelele. Ukusebenzisa izakhiwo zokupakishwa zendabuko ezisekelwe ku-silicon kumadivayisi wamandla we-wide-bandgap kungaletha izinkinga ezintsha nezinselele ezihlobene nokuvama, ukuphathwa kokushisa, kanye nokuthembeka. Amadivayisi wamandla we-SiC azwela kakhulu ku-capacitance ye-parasitic kanye ne-inductance. Uma kuqhathaniswa namadivayisi e-Si, ama-power chip e-SiC anesivinini sokushintsha esisheshayo, okungaholela ekuqhumeni ngokweqile, ukuzulazula, ukulahlekelwa kokushintsha okwandisiwe, kanye nokungasebenzi kahle kwedivayisi. Ngaphezu kwalokho, amadivayisi wamandla e-SiC asebenza emazingeni okushisa aphezulu, adinga amasu okuphatha ukushisa athuthukile kakhulu.
Kuye kwasungulwa izakhiwo ezahlukahlukene emkhakheni wokupakisha amandla e-semiconductor ebanzi. Ukupakisha kwemoduli yamandla yendabuko esekelwe ku-Si akusafaneleki. Ukuze kuxazululwe izinkinga zamapharamitha aphezulu e-parasitic kanye nokusebenza kahle kokusatshalaliswa kokushisa kwe-Si-based power module, ukupakisha kwemoduli yamandla ye-SiC kusebenzisa ukuxhumana okungenantambo kanye nobuchwepheshe bokupholisa obunezinhlangothi ezimbili esakhiweni sayo, futhi kusebenzisa nezinto ze-substrate ezine-conductivity engcono yokushisa, futhi kwazama ukuhlanganisa ama-capacitor okuhlukanisa, izinzwa zokushisa/zamanje, kanye nama-drive circuits esakhiweni semoduli, futhi kwathuthukiswa ubuchwepheshe obuhlukahlukene bokupakisha amamoduli. Ngaphezu kwalokho, kunezithiyo zobuchwepheshe eziphezulu ekukhiqizweni kwamadivayisi e-SiC kanye nezindleko zokukhiqiza ziphakeme.
Amadivayisi e-silicon carbide akhiqizwa ngokufaka izendlalelo ze-epitaxial ku-substrate ye-silicon carbide nge-CVD. Le nqubo ihilela ukuhlanza, ukushiswa kwe-oxidation, i-photolithography, ukuqopha, ukususa i-photoresist, ukufakwa kwe-ion, ukufakwa kwe-chemical vapor ye-silicon nitride, ukupholisha, ukusputtering, kanye nezinyathelo zokucubungula ezilandelayo zokwakha isakhiwo sedivayisi ku-substrate ye-SiC single crystal. Izinhlobo eziyinhloko zamadivayisi kagesi e-SiC zifaka phakathi ama-diode e-SiC, ama-transistors e-SiC, kanye namamojula kagesi e-SiC. Ngenxa yezici ezifana nesivinini sokukhiqiza izinto ezihamba kancane kanye namazinga aphansi okukhiqiza, amadivayisi e-silicon carbide anezindleko zokukhiqiza eziphakeme kakhulu.
Ngaphezu kwalokho, ukukhiqizwa kwamadivayisi e-silicon carbide kunezinkinga ezithile zobuchwepheshe:
1) Kuyadingeka ukuthuthukisa inqubo ethile ehambisana nezici zezinto ze-silicon carbide. Isibonelo: I-SiC inezinga eliphezulu lokuncibilika, okwenza ukusabalala kokushisa kwendabuko kungasebenzi kahle. Kuyadingeka ukusebenzisa indlela yokufaka i-ion nokulawula ngokunembile amapharamitha afana nokushisa, izinga lokushisa, ubude besikhathi, kanye nokugeleza kwegesi; I-SiC ayisebenzi ezinyibilikisi zamakhemikhali. Izindlela ezifana nokusika okomile kufanele zisetshenziswe, futhi izinto zemaski, izingxube zegesi, ukulawula ukuthambeka kwe-sidewall, izinga lokusika, ubulukhuni be-sidewall, njll. kufanele zilungiselelwe futhi zithuthukiswe;
2) Ukukhiqizwa kwama-electrode ensimbi kuma-wafer e-silicon carbide kudinga ukumelana nokuxhumana okungaphansi kuka-10-5Ω2. Izinto ze-electrode ezihlangabezana nezidingo, i-Ni ne-Al, zinokuzinza kokushisa okungekuhle okungaphezu kuka-100°C, kodwa i-Al/Ni inokuqina kokushisa okungcono. Ukumelana okuqondile kokuxhumana kwezinto ze-electrode ezihlanganisiwe ze-/W/Au kuphakeme ngo-10-3Ω2;
3) I-SiC inokuguga okuphezulu kokusika, kanti ubulukhuni be-SiC bulandela idayimane kuphela, okubeka phambili izidingo eziphakeme zokusika, ukugaya, ukupholisha kanye nobunye ubuchwepheshe.
Ngaphezu kwalokho, amadivayisi kagesi e-trench silicon carbide kunzima kakhulu ukuwakhiqiza. Ngokwezakhiwo ezahlukene zamadivayisi, amadivayisi kagesi e-silicon carbide angahlukaniswa kakhulu abe amadivayisi e-planar kanye namadivayisi e-trench. Amadivayisi kagesi e-Planar silicon carbide anokuhambisana okuhle kweyunithi kanye nenqubo elula yokukhiqiza, kodwa athambekele kumphumela we-JFET futhi anomthamo ophezulu we-parasite kanye nokumelana nesimo. Uma kuqhathaniswa namadivayisi e-planar, amadivayisi kagesi e-trench silicon carbide anokuhambisana okuphansi kweyunithi futhi anenqubo yokukhiqiza eyinkimbinkimbi kakhulu. Kodwa-ke, isakhiwo se-trench sivumela ukwandisa ubuningi beyunithi yedivayisi futhi cishe asikhiqizi umphumela we-JFET, okuwusizo ekuxazululeni inkinga yokuhamba kwesiteshi. Inezakhiwo ezinhle kakhulu njengokumelana okuncane, umthamo omncane we-parasite, kanye nokusetshenziswa kwamandla okushintshwa okuphansi. Inezindleko ezibalulekile kanye nezinzuzo zokusebenza futhi isibe yisiqondiso esiyinhloko sokuthuthukiswa kwamadivayisi kagesi e-silicon carbide. Ngokusho kwewebhusayithi esemthethweni yeRohm, isakhiwo se-ROHM Gen3 (isakhiwo se-Gen1 Trench) singama-75% kuphela endawo ye-chip ye-Gen2 (Plannar2), kanti ukumelana kwesakhiwo se-ROHM Gen3 kuncishiswe ngo-50% ngaphansi kosayizi ofanayo we-chip.
I-silicon carbide substrate, i-epitaxy, i-front-end, izindleko ze-R&D kanye nezinye zifaka u-47%, 23%, 19%, 6% kanye no-5% wezindleko zokukhiqiza amadivayisi e-silicon carbide ngokulandelana.
Okokugcina, sizogxila ekuhlukaniseni izithiyo zobuchwepheshe zezingxenye ezingaphansi kweketanga lemboni ye-silicon carbide.
Inqubo yokukhiqiza ama-substrate e-silicon carbide ifana neye-substrate esekelwe ku-silicon, kodwa inzima kakhulu.
Inqubo yokukhiqiza i-substrate ye-silicon carbide ngokuvamile ihlanganisa ukuhlanganiswa kwezinto zokusetshenziswa, ukukhula kwekristalu, ukucutshungulwa kwe-ingot, ukusika i-ingot, ukugaya i-wafer, ukupholisha, ukuhlanza nezinye izixhumanisi.
Isigaba sokukhula kwekristalu siwumgogodla wenqubo yonke, futhi lesi sinyathelo sinquma izakhiwo zikagesi ze-silicon carbide substrate.
Izinto ze-silicon carbide kunzima ukuzikhulisa esigabeni soketshezi ngaphansi kwezimo ezijwayelekile. Indlela yokukhula kwesigaba somusi ethandwa emakethe namuhla inokushisa kokukhula okungaphezu kuka-2300°C futhi idinga ukulawulwa okunembile kokushisa kokukhula. Inqubo yonke yokusebenza cishe kunzima ukuyibona. Iphutha elincane lizoholela ekususweni komkhiqizo. Uma kuqhathaniswa, izinto ze-silicon zidinga kuphela u-1600℃, okuphansi kakhulu. Ukulungiselela izisekelo ze-silicon carbide nakho kubhekene nobunzima obufana nokukhula kancane kwekristalu kanye nezidingo eziphezulu zesimo sekristalu. Ukukhula kwe-silicon carbide wafer kuthatha cishe izinsuku eziyi-7 kuya kweziyi-10, kuyilapho ukudonsa induku ye-silicon kuthatha izinsuku ezi-2 nesigamu kuphela. Ngaphezu kwalokho, i-silicon carbide iyinto enobunzima bayo obulandela idayimane kuphela. Izolahlekelwa kakhulu ngesikhathi sokusika, ukugaya, nokupholisha, kanti isilinganiso sokukhipha singama-60% kuphela.
Siyazi ukuthi umkhuba ukwandisa usayizi we-silicon carbide substrates, njengoba usayizi uqhubeka nokukhula, izidingo zobuchwepheshe bokukhulisa ububanzi ziya ngokuya ziphakama. Kudinga inhlanganisela yezinto ezahlukene zokulawula zobuchwepheshe ukuze kufezwe ukukhula okuphindaphindiwe kwamakristalu.
Isikhathi sokuthunyelwe: Meyi-22-2024