Mavuto aukadaulo pa ma wafer apamwamba a silicon carbide opanga zinthu zambiri komanso ogwira ntchito bwino ndi awa:
1) Popeza makhiristo amafunika kukula pamalo otentha kwambiri opitilira 2000°C, zofunikira pakuwongolera kutentha zimakhala zapamwamba kwambiri;
2) Popeza silicon carbide ili ndi mapangidwe a makristalo opitilira 200, koma mapangidwe ochepa okha a single-crystal silicon carbide ndi omwe amafunikira zinthu za semiconductor, chiŵerengero cha silicon-to-carbon, gradient ya kukula kwa kutentha, ndi kukula kwa makristalo ziyenera kulamulidwa bwino panthawi ya kukula kwa makristalo. Ma parameter monga liwiro ndi kuthamanga kwa mpweya;
3) Pansi pa njira yotumizira nthunzi, ukadaulo wokulitsa kukula kwa kristalo wa silicon carbide m'mimba mwake ndi wovuta kwambiri;
4) Kulimba kwa silicon carbide kuli pafupi ndi kwa diamondi, ndipo njira zodulira, kupukuta, ndi kupukuta ndizovuta.
Ma wafer a SiC epitaxial: nthawi zambiri amapangidwa pogwiritsa ntchito njira ya chemical vapor deposition (CVD). Malinga ndi mitundu yosiyanasiyana ya doping, amagawidwa m'magulu a n-type ndi p-type epitaxial wafers. Domestic Hantian Tiancheng ndi Dongguan Tianyu amatha kale kupereka ma wafer a SiC epitaxial a mainchesi 4/6. Kwa SiC epitaxy, n'kovuta kuwongolera m'munda wamagetsi amphamvu, ndipo mtundu wa SiC epitaxy umakhudza kwambiri zida za SiC. Kuphatikiza apo, zida za epitaxial zimagwiritsidwa ntchito ndi makampani anayi otsogola mumakampani: Axitron, LPE, TEL ndi Nuflare.
Silikoni carbide epitaxialWafer amatanthauza wafer wa silicon carbide momwe filimu imodzi ya kristalo (epitaxial layer) yokhala ndi zofunikira zinazake komanso zofanana ndi kristalo wa substrate imakulitsidwa pa substrate yoyambirira ya silicon carbide. Kukula kwa Epitaxial kumagwiritsa ntchito zida za CVD (Chemical Vapor Deposition, ) kapena zida za MBE (Molecular Beam Epitaxy). Popeza zida za silicon carbide zimapangidwa mwachindunji mu epitaxial layer, mtundu wa epitaxial layer umakhudza mwachindunji magwiridwe antchito ndi zokolola za chipangizocho. Pamene magetsi akupirira magwiridwe antchito a chipangizocho akupitilira kukula, makulidwe a epitaxial layer yofananayo amakhala okulirapo ndipo kuwongolera kumakhala kovuta kwambiri. Nthawi zambiri, pamene magetsi ali pafupi 600V, makulidwe ofunikira a epitaxial layer ndi pafupifupi 6 microns; pamene magetsi ali pakati pa 1200-1700V, makulidwe ofunikira a epitaxial layer amafika 10-15 microns. Ngati magetsi afika pa 10,000 volts, makulidwe a epitaxial layer opitilira 100 microns angafunike. Pamene makulidwe a epitaxial layer akupitirira kukwera, zimakhala zovuta kwambiri kuwongolera makulidwe ndi kukana kwa zinthu komanso kuchuluka kwa zolakwika.
Zipangizo za SiC: Padziko lonse lapansi, SiC SBD ndi MOSFET ya 600 ~ 1700V yakhala ikugwiritsidwa ntchito m'mafakitale. Zipangizo zazikuluzikulu zimagwira ntchito pamlingo wamagetsi pansi pa 1200V ndipo makamaka zimagwiritsa ntchito ma CD a TO. Ponena za mitengo, zinthu za SiC pamsika wapadziko lonse zimagulitsidwa pafupifupi nthawi 5-6 kuposa za Si. Komabe, mitengo ikutsika ndi 10% pachaka chifukwa cha kufalikira kwa zipangizo zokwera komanso kupanga zida m'zaka 2-3 zikubwerazi, kupezeka kwa msika kudzawonjezeka, zomwe zimabweretsa kutsika kwa mitengo. Zikuyembekezeka kuti mtengo ukafika nthawi 2-3 kuposa wa zinthu za Si, ubwino wobwera chifukwa cha kutsika kwa ndalama zomwe zimagwiritsidwa ntchito komanso magwiridwe antchito abwino pang'onopang'ono zidzapangitsa SiC kukhala pamsika wa zipangizo za Si.
Mapaketi achikhalidwe amachokera ku zinthu zopangidwa ndi silicon, pomwe zida za semiconductor za m'badwo wachitatu zimafuna kapangidwe katsopano. Kugwiritsa ntchito mapangidwe achikhalidwe opangidwa ndi silicon pazida zamagetsi zamtundu wa wide-bandgap kungayambitse mavuto atsopano okhudzana ndi ma frequency, kasamalidwe ka kutentha, komanso kudalirika. Zipangizo zamagetsi za SiC zimakhala zovuta kwambiri ku capacitance ya parasitic ndi inductance. Poyerekeza ndi zida za Si, ma chip amphamvu a SiC ali ndi liwiro losinthira mwachangu, zomwe zingayambitse kugwedezeka kwambiri, kugwedezeka, kutayika kwakukulu kwa kusintha, komanso ngakhale kulephera kwa chipangizo. Kuphatikiza apo, zida zamagetsi za SiC zimagwira ntchito kutentha kwambiri, zomwe zimafuna njira zapamwamba kwambiri zoyendetsera kutentha.
Mapangidwe osiyanasiyana apangidwa m'munda wa ma packaging amagetsi a semiconductor okhala ndi bandgap. Ma packaging amagetsi achikhalidwe okhala ndi Si-based power module salinso oyenera. Pofuna kuthetsa mavuto a ma partitions apamwamba komanso kusagwira bwino ntchito kwa ma packaging amagetsi achikhalidwe okhala ndi Si-based power module, ma packaging a SiC power module amagwiritsa ntchito ukadaulo wolumikizirana opanda zingwe komanso ukadaulo woziziritsa mbali ziwiri m'mapangidwe ake, komanso amagwiritsa ntchito zipangizo za substrate zokhala ndi ma conductivity abwino a kutentha, ndikuyesera kuphatikiza ma capacitor olumikizirana, masensa otenthetsera/amagetsi, ndi ma drive circuits mu kapangidwe ka ma module, ndikupanga ukadaulo wosiyanasiyana wophatikiza ma module. Kuphatikiza apo, pali zopinga zambiri zaukadaulo pakupanga zida za SiC ndi ndalama zopangira ndizokwera.
Zipangizo za silicon carbide zimapangidwa poika zigawo za epitaxial pa substrate ya silicon carbide kudzera mu CVD. Njirayi imaphatikizapo kuyeretsa, kusungunuka, kujambula, kupukuta, kuchotsa photoresist, kuyika ma ion, kuika silicon nitride ndi nthunzi ya mankhwala, kupukuta, kupopera, ndi njira zina zokonzera kuti apange kapangidwe ka chipangizocho pa substrate ya SiC single crystal. Mitundu ikuluikulu ya zipangizo zamagetsi za SiC ndi monga ma diode a SiC, ma transistors a SiC, ndi ma module amphamvu a SiC. Chifukwa cha zinthu monga liwiro lochepa lopanga zinthu komanso kuchuluka kochepa kwa zokolola, zipangizo za silicon carbide zimakhala ndi ndalama zambiri zopangira.
Kuphatikiza apo, kupanga zida za silicon carbide kuli ndi zovuta zina zaukadaulo:
1) Ndikofunikira kupanga njira inayake yomwe ikugwirizana ndi mawonekedwe a zinthu za silicon carbide. Mwachitsanzo: SiC ili ndi malo osungunuka kwambiri, zomwe zimapangitsa kuti kufalikira kwa kutentha kwachikhalidwe kusagwire ntchito. Ndikofunikira kugwiritsa ntchito njira yopangira ma ion implantation ndikuwongolera molondola magawo monga kutentha, kutentha, nthawi, ndi kuyenda kwa mpweya; SiC ndi yosagwira ntchito ku zosungunulira mankhwala. Njira monga kupukuta kouma ziyenera kugwiritsidwa ntchito, ndipo zinthu zophimba nkhope, zosakaniza za mpweya, kuwongolera kutsetsereka kwa mbali, kutentha, kukhwima kwa mbali, ndi zina zotero ziyenera kukonzedwa bwino ndikupangidwa;
2) Kupanga ma electrode achitsulo pa ma wafer a silicon carbide kumafuna kukana kwa contact pansi pa 10-5Ω2. Zipangizo za electrode zomwe zimakwaniritsa zofunikira, Ni ndi Al, zimakhala ndi kukhazikika kwa kutentha kopitilira 100°C, koma Al/Ni imakhala ndi kukhazikika kwa kutentha kopitilira. Kukana kwa contact specific kwa /W/Au composite electrode ndi 10-3Ω2 yokwera;
3) SiC imadula kwambiri, ndipo kuuma kwa SiC ndi kwachiwiri pambuyo pa diamondi, zomwe zimapangitsa kuti pakhale zofunikira kwambiri pakudula, kupera, kupukuta ndi ukadaulo wina.
Kuphatikiza apo, zida zamagetsi za trench silicon carbide zimakhala zovuta kupanga. Malinga ndi kapangidwe ka zida zosiyanasiyana, zida zamagetsi za silicon carbide zitha kugawidwa m'magulu a planar ndi zida za trench. Zida zamagetsi za planar silicon carbide zimakhala ndi unit consistency yabwino komanso njira yosavuta yopangira, koma zimakhala ndi JFET effect ndipo zimakhala ndi parasitic capacitance yayikulu komanso kukana kwa pa-state. Poyerekeza ndi zida za planar, zida zamagetsi za trench silicon carbide zimakhala ndi unit consistency yochepa ndipo zimakhala ndi njira yovuta kwambiri yopangira. Komabe, kapangidwe ka trench kamakhala kothandiza kuwonjezera kuchuluka kwa chipangizocho ndipo sikungathe kupanga JFET effect, zomwe ndizothandiza kuthetsa vuto la kuyenda kwa njira. Ili ndi zinthu zabwino kwambiri monga kukana pang'ono, parasitic capacitance yaying'ono, komanso kugwiritsa ntchito mphamvu zochepa. Ili ndi mtengo wofunikira komanso ubwino wogwirira ntchito ndipo yakhala njira yayikulu yopangira zida zamagetsi za silicon carbide. Malinga ndi tsamba lovomerezeka la Rohm, kapangidwe ka ROHM Gen3 (kapangidwe ka Gen1 Trench) ndi 75% yokha ya malo a chip a Gen2 (Plannar2), ndipo kukana kwa kapangidwe ka ROHM Gen3 kumachepetsedwa ndi 50% pansi pa kukula komweko kwa chip.
Ndalama za silicon carbide, epitaxy, front-end, R&D ndi zina ndi 47%, 23%, 19%, 6% ndi 5% ya ndalama zopangira zida za silicon carbide motsatana.
Pomaliza, tiyang'ana kwambiri pakuswa zopinga zaukadaulo za substrates mu unyolo wamakampani a silicon carbide.
Njira yopangira zinthu zopangidwa ndi silicon carbide ndi yofanana ndi ya zinthu zopangidwa ndi silicon, koma ndi yovuta kwambiri.
Njira yopangira silicon carbide substrate nthawi zambiri imaphatikizapo kupanga zinthu zopangira, kukula kwa kristalo, kukonza ingot, kudula ingot, kupera wafer, kupukuta, kuyeretsa ndi maulalo ena.
Gawo la kukula kwa kristalo ndilo maziko a ndondomeko yonse, ndipo gawoli limatsimikizira mphamvu zamagetsi za substrate ya silicon carbide.
Zipangizo za silicon carbide n'zovuta kubzala mu gawo lamadzimadzi pansi pa mikhalidwe yabwinobwino. Njira yokulira ya gawo la nthunzi yomwe imadziwika pamsika masiku ano ili ndi kutentha kwa kukula kopitilira 2300°C ndipo imafuna kuwongolera bwino kutentha kwa kukula. Njira yonse yogwirira ntchito ndi yovuta kuwona. Cholakwika chochepa chingayambitse kutaya zinthu. Poyerekeza, zipangizo za silicon zimangofunika 1600℃, zomwe ndizochepa kwambiri. Kukonzekera magawo a silicon carbide kumakumananso ndi zovuta monga kukula pang'onopang'ono kwa kristalo ndi zofunikira kwambiri pa mawonekedwe a kristalo. Kukula kwa silicon carbide wafer kumatenga masiku 7 mpaka 10, pomwe kukoka ndodo ya silicon kumatenga masiku awiri ndi theka okha. Kuphatikiza apo, silicon carbide ndi chinthu chomwe kuuma kwake kumakhala kwachiwiri kwa diamondi. Chidzatayika kwambiri podula, kupukuta, ndi kupukuta, ndipo chiŵerengero cha zotuluka ndi 60% yokha.
Tikudziwa kuti chizolowezi chake ndi kuwonjezera kukula kwa zinthu za silicon carbide, pamene kukula kukupitirira kukula, zofunikira pa ukadaulo wokulitsa kukula kwa dayamita zikukwera kwambiri. Zimafunika kuphatikiza zinthu zosiyanasiyana zowongolera ukadaulo kuti makhiristo apitirire kukula.
Nthawi yotumizira: Meyi-22-2024