Matsalolin fasaha a cikin wafers masu inganci na silicon carbide waɗanda ke samar da taro mai kyau tare da aiki mai karko sun haɗa da:
1) Tunda lu'ulu'u suna buƙatar girma a cikin yanayi mai zafi mai zafi sama da 2000°C, buƙatun sarrafa zafin jiki suna da matuƙar girma;
2) Tunda silicon carbide yana da tsarin lu'ulu'u sama da 200, amma kaɗan ne kawai tsarin lu'ulu'u na silicon carbide guda ɗaya ake buƙata, rabon silicon-da-carbon, canjin zafin jiki na girma, da haɓakar lu'ulu'u ya kamata a sarrafa su daidai lokacin tsarin girma lu'ulu'u. Sigogi kamar gudu da matsin lamba na iska;
3) A ƙarƙashin hanyar watsa tururin, fasahar faɗaɗa diamita na girman lu'ulu'u na silicon carbide yana da matuƙar wahala;
4) Taurin silicon carbide yana kusa da na lu'u-lu'u, kuma dabarun yankewa, niƙawa, da gogewa suna da wahala.
Wafers na epitaxial na SiC: galibi ana ƙera su ta hanyar amfani da hanyar adana tururin sinadarai (CVD). Dangane da nau'ikan doping daban-daban, an raba su zuwa wafers na epitaxial na n-type da p-type. Hantian Tiancheng da Dongguan Tianyu na gida sun riga sun iya samar da wafers na epitaxial na SiC mai inci 4/6-inch. Ga SiC epitaxy, yana da wuya a sarrafa shi a cikin filin ƙarfin lantarki mai girma, kuma ingancin SiC epitaxy yana da tasiri mafi girma akan na'urorin SiC. Bugu da ƙari, manyan kamfanoni huɗu a masana'antar suna da ikon mallakar kayan aikin epitaxial: Axitron, LPE, TEL da Nuflare.
Epitaxial na silicon carbideWafer yana nufin wafer ɗin silicon carbide wanda aka shuka fim ɗin kristal guda ɗaya (layin epitaxial) tare da wasu buƙatu kuma iri ɗaya da lu'ulu'u na substrate akan asalin silicon carbide substrate. Girman Epitaxial galibi yana amfani da kayan aikin CVD (Chemical Vapor Deposition, ) ko kayan aikin MBE (Molecular Beam Epitaxy). Tunda ana ƙera na'urorin silicon carbide kai tsaye a cikin layin epitaxial, ingancin layin epitaxial yana shafar aiki da yawan amfanin na'urar kai tsaye. Yayin da aikin juriyar ƙarfin lantarki na na'urar ke ci gaba da ƙaruwa, kauri na layin epitaxial mai dacewa yana yin kauri kuma ikon sarrafawa yana ƙara wahala. Gabaɗaya, lokacin da ƙarfin lantarki yake kusa da 600V, kauri na layin epitaxial da ake buƙata shine kusan microns 6; lokacin da ƙarfin lantarki yake tsakanin 1200-1700V, kauri na layin epitaxial da ake buƙata ya kai microns 10-15. Idan ƙarfin lantarki ya kai fiye da volts 10,000, ana iya buƙatar kauri na layin epitaxial fiye da microns 100. Yayin da kauri na epitaxial Layer ke ci gaba da ƙaruwa, yana ƙara zama da wahala a sarrafa kauri da juriya daidai da yawan lahani.
Na'urorin SiC: A ƙasashen duniya, 600~1700V SiC SBD da MOSFET sun kasance masana'antu. Manyan kayayyakin suna aiki a matakan ƙarfin lantarki ƙasa da 1200V kuma galibi suna amfani da TO marufi. Dangane da farashi, samfuran SiC a kasuwar duniya ana farashin su da kusan sau 5-6 fiye da takwarorinsu na Si. Duk da haka, farashi yana raguwa a ƙimar shekara-shekara na 10%. Tare da faɗaɗa kayan sama da samar da na'urori a cikin shekaru 2-3 masu zuwa, wadatar kasuwa za ta ƙaru, wanda ke haifar da ƙarin raguwar farashi. Ana sa ran lokacin da farashin ya kai ninki 2-3 na samfuran Si, fa'idodin da ke tattare da rage farashin tsarin da ingantaccen aiki za su sa SiC ta mamaye kasuwar na'urorin Si a hankali.
Marufi na gargajiya ya dogara ne akan abubuwan da aka yi da silicon, yayin da kayan semiconductor na ƙarni na uku suna buƙatar sabon ƙira gaba ɗaya. Yin amfani da tsarin marufi na gargajiya na silicon don na'urorin wutar lantarki masu faɗi-faɗi na iya gabatar da sabbin matsaloli da ƙalubale da suka shafi mita, sarrafa zafi, da aminci. Na'urorin wutar lantarki na SiC sun fi saurin kamuwa da ƙarfin parasitic da inductance. Idan aka kwatanta da na'urorin Si, guntun wutar lantarki na SiC suna da saurin sauyawa, wanda zai iya haifar da overshoot, juyawa, ƙaruwar asarar sauyawa, har ma da matsalolin na'ura. Bugu da ƙari, na'urorin wutar lantarki na SiC suna aiki a yanayin zafi mafi girma, suna buƙatar dabarun sarrafa zafi mafi girma.
An ƙirƙiro nau'ikan tsare-tsare daban-daban a fannin faifan wutar lantarki na semiconductor mai faɗi. Faifan wutar lantarki na gargajiya na Si ba shi da dacewa. Domin magance matsalolin manyan sigogin parasites da rashin ingancin watsa zafi na marufi na Si na gargajiya, marufi na SiC na lantarki yana amfani da haɗin mara waya da fasahar sanyaya gefe biyu a cikin tsarinsa, kuma yana ɗaukar kayan substrate tare da ingantaccen watsa zafi, kuma yana ƙoƙarin haɗa capacitors, firikwensin zafin jiki/na yanzu, da da'irori masu tuƙi cikin tsarin module, kuma ya haɓaka fasahar marufi iri-iri. Bugu da ƙari, akwai manyan shinge na fasaha ga kera na'urorin SiC kuma farashin samarwa yana da yawa.
Ana samar da na'urorin silicon carbide ta hanyar sanya layukan epitaxial akan wani abu mai silicon carbide ta hanyar CVD. Tsarin ya haɗa da tsaftacewa, oxidation, photolithography, etching, cire photoresist, dasa ion, adana tururin sinadarai na silicon nitride, gogewa, sputtering, da kuma matakan sarrafawa masu zuwa don samar da tsarin na'urar akan silinda guda ɗaya na SiC. Manyan nau'ikan na'urorin wutar lantarki na SiC sun haɗa da diodes na SiC, transistors na SiC, da kuma na'urorin wutar lantarki na SiC. Saboda dalilai kamar jinkirin saurin samar da kayan sama da ƙarancin yawan amfanin ƙasa, na'urorin silicon carbide suna da tsadar masana'antu.
Bugu da ƙari, kera na'urorin silicon carbide yana da wasu matsaloli na fasaha:
1) Ya zama dole a samar da takamaiman tsari wanda ya yi daidai da halayen kayan silicon carbide. Misali: SiC yana da babban wurin narkewa, wanda ke sa yaduwar zafi ta gargajiya ba ta da tasiri. Ya zama dole a yi amfani da hanyar dasa ion da kuma sarrafa sigogi daidai kamar zafin jiki, saurin dumama, tsawon lokaci, da kwararar iskar gas; SiC ba ya shiga cikin sinadarai masu narkewa. Ya kamata a yi amfani da hanyoyi kamar busassun etching, kuma a inganta kayan rufe fuska, cakuda iskar gas, sarrafa gangaren gefe, saurin etching, ƙaiƙayin gefen gefe, da sauransu;
2) Yin amfani da na'urorin lantarki na ƙarfe akan wafers na silicon carbide yana buƙatar juriyar hulɗa a ƙasa da 10-5Ω2. Kayan lantarki waɗanda suka cika buƙatun, Ni da Al, suna da ƙarancin kwanciyar hankali na zafi sama da 100°C, amma Al/Ni yana da ingantaccen kwanciyar hankali na zafi. Juriyar hulɗa ta musamman ta kayan lantarki masu haɗaka /W/Au ya fi 10-3Ω2 girma;
3) SiC yana da yawan lalacewa ta hanyar yankewa, kuma taurin SiC ya fi na lu'u-lu'u, wanda ke gabatar da manyan buƙatu don yankewa, niƙawa, gogewa da sauran fasahohi.
Bugu da ƙari, na'urorin wutar lantarki na silicon carbide suna da wahalar ƙerawa. Dangane da tsarin na'urori daban-daban, ana iya raba na'urorin wutar lantarki na silicon carbide zuwa na'urori masu siffar planar da na'urorin rami. Na'urorin wutar lantarki na silicon carbide na Planar suna da daidaiton na'ura mai kyau da kuma sauƙin sarrafawa, amma suna da saurin tasirin JFET kuma suna da ƙarfin parasitic da juriya a kan yanayin. Idan aka kwatanta da na'urorin planar, na'urorin wutar lantarki na silicon carbide na trench suna da ƙarancin daidaiton na'ura kuma suna da tsari mai rikitarwa. Duk da haka, tsarin ramin yana da amfani wajen ƙara yawan na'urar kuma ba shi da yuwuwar samar da tasirin JFET, wanda ke da amfani wajen magance matsalar motsi na tashoshi. Yana da kyawawan halaye kamar ƙananan juriya akan-kan-kan, ƙaramin ƙarfin parasitic, da ƙarancin amfani da makamashi. Yana da fa'idodi masu mahimmanci na farashi da aiki kuma ya zama babban alkiblar haɓaka na'urorin wutar lantarki na silicon carbide. A cewar gidan yanar gizon Rohm, tsarin ROHM Gen3 (tsarin Gen1 Trench) shine kashi 75% kawai na yankin guntu na Gen2 (Plannar2), kuma juriyar tsarin ROHM Gen3 ta ragu da kashi 50% a ƙarƙashin girman guntu ɗaya.
Kuɗaɗen silicon carbide, epitaxy, front-end, R&D da sauransu sun kai kashi 47%, 23%, 19%, 6% da 5% na kuɗin ƙera na'urorin silicon carbide bi da bi.
A ƙarshe, za mu mayar da hankali kan warware shingayen fasaha na substrates a cikin sarkar masana'antar silicon carbide.
Tsarin samar da sinadaran silicon carbide yana kama da na sinadaran silicon, amma ya fi wahala.
Tsarin kera sinadarin silicon carbide gabaɗaya ya haɗa da haɗakar kayan abu, haɓakar lu'ulu'u, sarrafa ingot, yanke ingot, niƙa wafer, gogewa, tsaftacewa da sauran hanyoyin haɗi.
Matakin girma na lu'ulu'u shine ginshiƙin dukkan tsarin, kuma wannan matakin yana ƙayyade halayen lantarki na silicon carbide substrate.
Kayan silicon carbide suna da wahalar girma a yanayin ruwa a ƙarƙashin yanayi na yau da kullun. Hanyar haɓakar tururi da aka shahara a kasuwa a yau tana da zafin girma sama da 2300°C kuma tana buƙatar cikakken iko akan zafin girma. Duk tsarin aiki yana da wuyar gani. Ƙaramin kuskure zai haifar da goge samfura. Idan aka kwatanta, kayan silicon suna buƙatar 1600℃ kawai, wanda ya fi ƙasa da haka. Shirya abubuwan silicon carbide suma suna fuskantar matsaloli kamar haɓakar lu'ulu'u a hankali da buƙatun siffar lu'ulu'u masu yawa. Girman wafer na silicon carbide yana ɗaukar kimanin kwanaki 7 zuwa 10, yayin da jan sandar silicon yana ɗaukar kwanaki 2 da rabi kawai. Bugu da ƙari, silicon carbide abu ne wanda taurinsa ya fi na lu'ulu'u. Zai yi asara mai yawa yayin yankewa, niƙawa, da gogewa, kuma rabon fitarwa shine kashi 60% kawai.
Mun san cewa yanayin shine ƙara girman abubuwan silicon carbide, yayin da girman ke ci gaba da ƙaruwa, buƙatun fasahar faɗaɗa diamita suna ƙaruwa. Yana buƙatar haɗakar abubuwan sarrafawa daban-daban na fasaha don cimma ci gaban lu'ulu'u masu maimaitawa.
Lokacin Saƙo: Mayu-22-2024