Ubunzima bezobuchwepheshe ekukhiqizeni ngokuzinzile amawafa e-silicon carbide ekhwalithi ephezulu asebenza ngokuzinzile ahlanganisa:
1) Njengoba amakristalu edinga ukukhula endaweni evalwe ngezinga lokushisa eliphezulu ngaphezu kuka-2000°C, izidingo zokulawula izinga lokushisa ziphezulu kakhulu;
2) Njengoba i-silicon carbide inezinhlaka zekristalu ezingaphezu kuka-200, kodwa kuphela izakhiwo ezimbalwa ze-single-crystal silicon carbide eziyizinto ezidingekayo ze-semiconductor, isilinganiso se-silicon-to-carbon, izinga lokushisa lokukhula, nokukhula kwekristalu kudinga ukulawulwa ngokunembile ngesikhathi. inqubo yokukhula kwekristalu. Amapharamitha afana nesivinini kanye nomfutho wokugeleza komoya;
I-3) Ngaphansi kwendlela yokudlulisa isigaba somoya, ubuchwepheshe bokunwetshwa kobubanzi be-silicon carbide crystal ukukhula bunzima kakhulu;
4) Ukuqina kwe-silicon carbide kuseduze nokwedayimane, futhi amasu okusika, ukugaya, nokupholisha anzima.
Ama-wafers e-SiC epitaxial: ngokuvamile akhiqizwa indlela ye-chemical vapor deposition (CVD). Ngokuya ngezinhlobo ezihlukene ze-doping, zihlukaniswe ngama-wafers e-epitaxial we-n-type kanye nohlobo lwe-p. U-Hantian Tiancheng wasekhaya kanye no-Dongguan Tianyu sebengakwazi kakade ukunikeza ama-SiC epitaxial wafers angu-4-intshi/6-intshi. Ku-SiC epitaxy, kunzima ukulawula endaweni yamandla kagesi aphezulu, futhi ikhwalithi ye-SiC epitaxy inomthelela omkhulu kumadivayisi we-SiC. Ngaphezu kwalokho, imishini ye-epitaxial ilawulwa yizinkampani ezine ezihamba phambili embonini: i-Axitron, i-LPE, i-TEL ne-Nuflare.
I-silicon carbide epitaxiali-wafer ibhekisela ku-silicon carbide wafer lapho ifilimu yekristalu eyodwa (ungqimba lwe-epitaxial) enezidingo ezithile futhi efanayo nekristalu engaphansi etshalwa ku-silicon carbide substrate yokuqala. Ukukhula kwe-Epitaxial ikakhulukazi kusebenzisa i-CVD (Chemical Vapor Deposition, ) okokusebenza noma okokusebenza kwe-MBE (Molecular Beam Epitaxy). Njengoba amadivaysi e-silicon carbide enziwa ngokuqondile kungqimba lwe-epitaxial, ikhwalithi ye-epitaxial layer ithinta ngokuqondile ukusebenza kanye nesivuno sedivayisi. Njengoba i-voltage ukumelana nokusebenza kwedivayisi iqhubeka nokwanda, ubukhulu bengqimba ye-epitaxial ehambisanayo iba mkhulu futhi ukulawula kuba nzima nakakhulu.Ngokuvamile, lapho i-voltage iseduze ne-600V, ubukhulu be-epitaxial layer edingekayo bungaba ngama-microns angu-6; lapho i-voltage iphakathi kuka-1200-1700V, ubukhulu be-epitaxial layer edingekayo bufinyelela ku-10-15 microns. Uma i-voltage ifinyelela ngaphezu kwama-volts angu-10,000, kungase kudingeke ugqinsi lwe-epitaxial engaphezu kwama-microns angu-100. Njengoba ukushuba kongqimba lwe-epitaxial buqhubeka nokwanda, kuba nzima nakakhulu ukulawula ukujiya nokufana kokumelana nokuminyana kwesici.
Amadivayisi e-SiC: Emazweni ngamazwe, i-600 ~ 1700V SiC SBD kanye ne-MOSFET yenziwe ngezimboni. Imikhiqizo evamile isebenza kumazinga kagesi angaphansi kuka-1200V futhi ngokuyinhloko isebenzisa i-TO package. Mayelana namanani entengo, imikhiqizo ye-SiC emakethe yamazwe ngamazwe inentengo cishe izikhathi ezi-5-6 ngaphezu kozakwabo bakwa-Si. Nokho, amanani ehla ngenani lonyaka lika-10%. ngokwandiswa kwezinto zokwakha ezikhuphuka nomfula kanye nokukhiqizwa kwedivayisi eminyakeni engu-2-3 ezayo, ukunikezwa kwemakethe kuzokhuphuka, okuholela ekuncishisweni okwengeziwe kwamanani. Kulindeleke ukuthi uma intengo ifinyelela izikhathi ezingu-2-3 kunemikhiqizo ye-Si, izinzuzo ezilethwa izindleko ezincishisiwe zesistimu nokusebenza okuthuthukisiwe kuzoshayela kancane kancane i-SiC ukuthi ithathe indawo yemakethe yamadivayisi we-Si.
Ukupakishwa kwendabuko kusekelwe kuma-substrates asekelwe ku-silicon, kuyilapho izinto ze-semiconductor yesizukulwane sesithathu zidinga umklamo omusha ngokuphelele. Ukusebenzisa izakhiwo zokupakisha ezisekelwe ku-silicon zamadivayisi wamandla we-wide-bandgap kungethula izinkinga ezintsha nezinselele ezihlobene nobuningi, ukuphathwa okushisayo, nokuthembeka. Amadivayisi kagesi e-SiC azwela kakhulu amandla e-parasitic kanye ne-inductance. Uma kuqhathaniswa namadivayisi we-Si, ama-chips wamandla we-SiC anesivinini sokushintsha ngokushesha, esingaholela ekudubuleni, ukunyakazisa, ukulahlekelwa okukhulayo kokushintsha, kanye nokungasebenzi kahle kwedivayisi. Ukwengeza, amadivayisi kagesi e-SiC asebenza emazingeni okushisa aphezulu, adinga amasu okuphatha okushisayo athuthuke kakhulu.
Izinhlobonhlobo zezakhiwo ezihlukene zenziwe emkhakheni wokupakishwa kwamandla we-wide-bandgap semiconductor. Ukupakishwa kwemojula ye-Si-based yendabuko ayisafaneleki. Ukuze kuxazululwe izinkinga zamapharamitha aphezulu we-parasitic kanye nokusebenza kahle kokushabalaliswa kokushisa okungekuhle kokupakishwa kwemojula ye-Si-based power module, ukupakishwa kwemojula yamandla we-SiC kusebenzisa ukuxhumana okungenantambo kanye nobuchwepheshe bokupholisa obuseceleni okukabili esakhiweni sayo, futhi yamukela izinto ze-substrate ezinokushisa okungcono kakhulu. conductivity, futhi yazama ukuhlanganisa ama-capacitor e-decoupling, izinga lokushisa/izinzwa zamanje, kanye nokushayela amasekethe esakhiweni semojula, futhi kwathuthukisa ukupakishwa kwamamojula ahlukahlukene. ubuchwepheshe. Ngaphezu kwalokho, kunezithiyo eziphezulu zobuchwepheshe zokukhiqiza idivayisi ye-SiC nezindleko zokukhiqiza ziphezulu.
Amadivayisi we-silicon carbide akhiqizwa ngokufaka izendlalelo ze-epitaxial ku-silicon carbide substrate nge-CVD. Le nqubo ihilela ukuhlanza, i-oxidation, i-photolithography, i-etching, ukukhumula i-photoresist, ukufakwa kwe-ion, ukufakwa kwamakhemikhali amakhemikhali e-silicon nitride, ukupholisha, ukuphalaza, kanye nezinyathelo zokucubungula ezilandelayo ukuze kwakhiwe isakhiwo sedivayisi ku-SiC single crystal substrate. Izinhlobo eziyinhloko zamadivayisi kagesi we-SiC zifaka ama-SiC diode, ama-SiC transistors, namamojula wamandla we-SiC. Ngenxa yezici ezifana nesivinini sokukhiqiza esihamba kancane esikhuphuka nomfula kanye namazinga aphansi esivuno, amadivayisi we-silicon carbide anezindleko zokukhiqiza eziphakeme kakhulu.
Ngaphezu kwalokho, ukukhiqizwa kwedivayisi ye-silicon carbide kunezinkinga ezithile zobuchwepheshe:
1) Kudingeka ukuthuthukisa inqubo ethile ehambisana nezici zezinto ze-silicon carbide. Isibonelo: I-SiC inezinga eliphezulu lokuncibilika, okwenza ukusakazeka kokushisa okungokwesiko kungasebenzi. Kudingekile ukusebenzisa indlela yokufaka i-ion doping nokulawula ngokunembile imingcele efana nezinga lokushisa, izinga lokushisa, ubude besikhathi, nokugeleza kwegesi; I-SiC iyizincibilikisi zamakhemikhali. Izindlela ezifana nokufaka okomile kufanele kusetshenziswe, futhi izinto zokufihla ubuso, izingxube zegesi, ukulawula ukuthambekela kodonga oluseceleni, izinga lokunamathisela, ukuhwashala kwezindonga eziseceleni, njll. kufanele kuthuthukiswe futhi kuthuthukiswe;
2) Ukwenziwa kwama-electrode ensimbi kuma-wafers e-silicon carbide kudinga ukumelana nokuxhumana ngaphansi kuka-10-5Ω2. Izinto ze-electrode ezihlangabezana nezidingo, i-Ni ne-Al, zinokuzinza okuphansi kwe-thermal ngaphezu kuka-100 ° C, kodwa i-Al/Ni inokusimama okungcono kwe-thermal. Ukumelana okuqondile kokuxhumana kwe-electrode eyinhlanganisela ye-/W/A kuphakeme ngo-10-3Ω2;
I-3) I-SiC inokugqoka okuphezulu kokusika, futhi ubulukhuni be-SiC bungokwesibili kuphela kwedayimane, okubeka phambili izidingo eziphakeme zokusika, ukugaya, ukupholisha nobunye ubuchwepheshe.
Ngaphezu kwalokho, amadivaysi kagesi we-silicon carbide anzima kakhulu ukwenza. Ngokusho kwezinhlaka ezahlukene zedivayisi, amadivayisi wamandla we-silicon carbide angahlukaniswa ikakhulukazi ngamadivaysi e-planar kanye namadivayisi omsele. Amadivayisi kagesi we-Planar silicon carbide anokulingana okuhle kweyunithi kanye nenqubo elula yokukhiqiza, kodwa athambekele kumphumela we-JFET futhi anamandla aphezulu we-parasitic kanye nokumelana nesimo. Uma kuqhathaniswa namadivayisi we-planar, amadivayisi wamandla we-trench silicon carbide anokulingana okuphansi kweyunithi futhi anenqubo yokukhiqiza eyinkimbinkimbi. Nokho, ukwakheka komsele kusiza ekwandiseni ukuminyana kweyunithi yedivayisi futhi mancane amathuba okuthi ukhiqize umphumela we-JFET, onenzuzo ekuxazululeni inkinga yokuhamba kwesiteshi. Inezici ezinhle kakhulu ezifana ne-on-resistance encane, i-parasitic capacitance encane, nokusebenzisa amandla okushintshwa okuphansi. Inezinzuzo ezibalulekile zezindleko nokusebenza futhi isiphenduke inkomba evamile yokuthuthukiswa kwamadivayisi wamandla we-silicon carbide. Ngokusho kwewebhusayithi esemthethweni ye-Rohm, isakhiwo se-ROHM Gen3 (isakhiwo se-Gen1 Trench) singama-75% kuphela wendawo ye-chip ye-Gen2 (Plannar2), futhi ukumelana kwesakhiwo se-ROHM Gen3 kuncipha ngo-50% ngaphansi kosayizi we-chip ofanayo.
I-silicon carbide substrate, i-epitaxy, i-front-end, izindleko ze-R&D nezinye zenza u-47%, u-23%, u-19%, u-6% no-5% wezindleko zokukhiqiza imishini ye-silicon carbide ngokulandelana.
Okokugcina, sizogxila ekwephuleni izithiyo zobuchwepheshe zama-substrates ochungechungeni lwemboni ye-silicon carbide.
Inqubo yokukhiqiza ye-silicon carbide substrates ifana neye-silicon-based substrates, kodwa inzima kakhulu.
Inqubo yokukhiqiza ye-silicon carbide substrate ngokuvamile ihlanganisa ukuhlanganiswa kwezinto ezingavuthiwe, ukukhula kwekristalu, ukucubungula ingot, ukusika ingot, ukugaya i-wafer, ukupholisha, ukuhlanza nezinye izixhumanisi.
Isigaba sokukhula kwekristalu siwumgogodla wayo yonke inqubo, futhi lesi sinyathelo sinquma izakhiwo zikagesi ze-silicon carbide substrate.
Izinto ze-silicon carbide zinzima ukukhula esigabeni samanzi ngaphansi kwezimo ezijwayelekile. Indlela yokukhula kwesigaba somhwamuko ethandwa kakhulu emakethe namuhla inezinga lokushisa elingaphezu kuka-2300°C futhi idinga ukulawulwa okunembile kwezinga lokushisa lokukhula. Yonke inqubo yokusebenza cishe kunzima ukuyibuka. Iphutha elincane lizoholela ekukhishweni komkhiqizo. Uma kuqhathaniswa, izinto ze-silicon zidinga kuphela i-1600 ℃, ephansi kakhulu. Ukulungiselela ama-silicon carbide substrates nakho kubhekana nobunzima obunjengokukhula kancane kwekristalu kanye nezidingo zefomu lekristalu eliphakeme. Ukukhula kwe-silicon carbide wafer kuthatha cishe izinsuku eziyi-7 kuye kweziyi-10, kuyilapho ukudonsa kwenduku ye-silicon kuthatha izinsuku ezi-2 nengxenye kuphela. Ngaphezu kwalokho, i-silicon carbide iyinto eqinile okuqina kwayo okwesibili kunedayimane. Izolahlekelwa kakhulu ngesikhathi sokusika, ukugaya, nokupholisha, futhi isilinganiso sokuphumayo singama-60%.
Siyazi ukuthi umkhuba owokukhuphula usayizi wama-silicon carbide substrates, njengoba usayizi uqhubeka nokukhula, izidingo zobuchwepheshe bokunwetshwa kobubanzi ziya ngokuya ziba phezulu. Kudinga inhlanganisela yezinto ezihlukahlukene zokulawula ubuchwepheshe ukuze kuzuzwe ukukhula okuphindaphindayo kwamakristalu.
Isikhathi sokuthumela: May-22-2024