A halin yanzu, masana'antar SiC tana canzawa daga 150 mm (inci 6) zuwa 200 mm (inci 8). Don saduwa da buƙatun gaggawa na manyan-size, high quality-SiC homoepitaxial wafers a cikin masana'antu, 150mm da 200mm4H-SiC homoepitaxial wafersan yi nasarar shirya su akan kayan aikin gida ta hanyar amfani da kayan haɓaka mai zaman kansa na 200mm SiC na ci gaban epitaxial. An samar da tsari na homoepitaxial wanda ya dace da 150mm da 200mm, wanda girman girman epitaxial zai iya girma fiye da 60um/h. Duk da yake saduwa da babban saurin epitaxy, ingancin wafer na epitaxial yana da kyau. Daidaitaccen kauri na 150 mm da 200 mmSiC epitaxial wafersana iya sarrafa shi a cikin 1.5%, daidaituwar maida hankali ya kasance ƙasa da 3%, ƙarancin lahani mai ƙarancin ƙarancin ƙasa da 0.3 barbashi / cm2, kuma tushen ƙaƙƙarfan tushe na epitaxial yana nufin murabba'in Ra bai wuce 0.15nm ba, kuma duk mahimman alamun tsari suna a matakin ci gaba na masana'antu.
Silicon Carbide (SiC)yana ɗaya daga cikin wakilan na'urorin semiconductor na ƙarni na uku. Yana da halaye na ƙarfin fashewar filin, ingantacciyar wutar lantarki, babban saurin jikewar wutar lantarki, da ƙarfin juriya mai ƙarfi. Ya haɓaka ƙarfin sarrafa makamashi na na'urorin lantarki kuma yana iya saduwa da bukatun sabis na kayan aikin lantarki na gaba na gaba don na'urorin da ke da iko mai girma, ƙananan ƙananan, yawan zafin jiki, high radiation da sauran matsanancin yanayi. Zai iya rage sarari, rage yawan amfani da wutar lantarki da rage buƙatun sanyaya. Ya kawo sauye-sauye na juyin juya hali ga sabbin motocin makamashi, sufurin jirgin kasa, grid mai wayo da sauran fannoni. Saboda haka, silicon carbide semiconductor an gane a matsayin manufa kayan da zai jagoranci na gaba ƙarni na high-ikon lantarki na'urorin. A cikin 'yan shekarun nan, godiya ga goyon bayan manufofin kasa da kasa kan raya masana'antu na semiconductor na ƙarni na uku, an kammala bincike da bunƙasa da gina tsarin masana'antar SiC mai tsawon mita 150 a kasar Sin, kuma tsaron sarkar masana'antu ya yi tasiri. a m garanti. Sabili da haka, mayar da hankali kan masana'antu a hankali ya canza zuwa kula da farashi da inganta ingantaccen aiki. Kamar yadda aka nuna a cikin Tebu 1, idan aka kwatanta da 150 mm, 200 mm SiC yana da ƙimar amfani mafi girma, kuma ana iya ƙara fitar da kwakwalwan wafer guda ɗaya da kusan sau 1.8. Bayan fasahar balagagge, ana iya rage farashin masana'anta na guntu ɗaya da kashi 30%. Ci gaban fasaha na 200 mm hanya ce ta kai tsaye na "rage farashi da haɓaka aiki", kuma shine mabuɗin masana'antar semiconductor na ƙasata don "gudanar da layi ɗaya" ko ma "jagoranci".
Daban-daban da tsarin na'urar Si,SiC semiconductor ikon na'urorinduk ana sarrafa su kuma an shirya su tare da yadudduka na epitaxial a matsayin ginshiƙi. Epitaxial wafers sune mahimman kayan asali don na'urorin wutar lantarki na SiC. Ingancin Layer epitaxial kai tsaye yana ƙayyade yawan amfanin na'urar, kuma farashin sa ya kai kashi 20% na farashin kera guntu. Saboda haka, haɓakar epitaxial shine muhimmiyar hanyar haɗin gwiwa a cikin na'urorin wutar lantarki na SiC. Matsakaicin girman matakin matakin tsarin epitaxial an ƙaddara ta kayan aikin epitaxial. A halin yanzu, matakin mayar da matakin 150mm SiC kayan aikin epitaxial a kasar Sin yana da inganci, amma gaba daya tsarin 200mm ya koma bayan matakin kasa da kasa a lokaci guda. Sabili da haka, don magance matsalolin gaggawa na gaggawa da matsalolin ƙwanƙwasa na manyan-size, high quality-epitaxial material masana'antu don ci gaban na gida na uku ƙarni na semiconductor masana'antu, wannan takarda gabatar da 200 mm SiC epitaxial kayan aiki samu nasarar ci gaba a cikin ƙasata. da kuma nazarin tsarin epitaxial. Ta hanyar inganta sigogi na tsari kamar yanayin zafin jiki, ƙimar iskar gas mai ɗaukar nauyi, rabon C / Si, da dai sauransu, daidaituwar daidaituwa <3%, rashin daidaituwa na kauri <1.5%, roughness Ra <0.2 nm da ƙarancin lahani mai ƙima <0.3 hatsi / cm2 na 150 mm da 200 mm SiC epitaxial wafers tare da mai zaman kansa 200 mm silicon carbide epitaxial tanderun aka samu. Matakin aiwatar da kayan aiki na iya biyan buƙatun shirye-shiryen na'urar wutar lantarki mai ƙarfi na SiC.
1 Gwaji
1.1 Ka'idarSiC epitaxialtsari
Tsarin girma na homoepitaxial na 4H-SiC ya ƙunshi matakai maɓalli guda 2, wato, babban zafin jiki a cikin wurin etching na 4H-SiC substrate da tsari na jigilar sinadari mai kama da juna. Babban manufar substrate in-situ etching shi ne don cire subsurface lalacewar da substrate bayan wafer polishing, saura polishing ruwa, barbashi da oxide Layer, da kuma na yau da kullum atomic mataki tsarin za a iya kafa a kan substrate surface ta etching. Ana yin etching a cikin wurin yawanci a cikin yanayin hydrogen. Dangane da ainihin abubuwan da ake buƙata na tsari, ana iya ƙara ƙaramin adadin iskar gas, kamar hydrogen chloride, propane, ethylene ko silane. Yawan zafin jiki na in-situ hydrogen etching yana gabaɗaya sama da 1 600 ℃, kuma ana sarrafa matsi na ɗakin amsa gabaɗaya a ƙasa 2 × 104 Pa yayin aiwatar da etching.
Bayan an kunna substrate surface ta in-wuri etching, ya shiga cikin high-zazzabi sinadaran tururi tsarin jijiya, wato, girma tushen (kamar ethylene/propane, TCS/silane), doping source (n-type doping source nitrogen). , p-type doping source TMAl), da iskar gas irin su hydrogen chloride ana jigilar su zuwa ɗakin amsawa ta hanyar babban iskar gas mai ɗaukar kaya (yawanci hydrogen). Bayan da iskar gas ya amsa a cikin babban dakin amsawa mai zafi, wani ɓangare na precursor yana amsa sinadarai da adsorbs akan farfajiyar wafer, kuma wani nau'in lu'u-lu'u mai kama da 4H-SiC epitaxial Layer tare da ƙayyadaddun maida hankali na doping, ƙayyadaddun kauri, kuma an kafa inganci mafi girma. a kan substrate surface ta amfani da guda-crystal 4H-SiC substrate a matsayin samfuri. Bayan shekaru na binciken fasaha, fasahar homoepitaxial ta 4H-SiC ta girma kuma ana amfani da ita sosai wajen samar da masana'antu. Fasahar homoepitaxial 4H-SiC da aka fi amfani da ita a duniya tana da halaye guda biyu:
(1) Yin amfani da kashe-axis (dangi da <0001> crystal jirgin sama, zuwa ga <11-20> crystal shugabanci) oblique yanke substrate a matsayin samfuri, high-tsarki guda-crystal 4H-SiC epitaxial Layer ba tare da ƙazanta ba ne. ajiya a kan substrate a cikin nau'i na mataki-flow girma yanayin. Farkon haɓakar homoepitaxial na 4H-SiC ya yi amfani da madaidaicin madaidaicin kristal, wato, <0001> Si jirgin don girma. Girman matakan atomic akan saman madaidaicin madaidaicin kristal yana da ƙasa kuma filaye suna da faɗi. Girman nucleation mai girma biyu yana da sauƙi don faruwa yayin tsarin epitaxy don samar da 3C crystal SiC (3C-SiC). By kashe-axis yankan, high-yawa, kunkuntar terrace nisa atomic matakai za a iya gabatar a kan surface na 4H-SiC <0001> substrate, da kuma adsorbed precursor iya yadda ya kamata isa atomic mataki matsayi tare da in mun gwada da low surface makamashi ta surface yadawa. . A mataki, precursor atom / kwayoyin halitta matsayin bonding matsayi ne na musamman, don haka a cikin mataki kwarara girma yanayin, da epitaxial Layer iya daidai gaji Si-C biyu atomic Layer stacking jerin na substrate don samar da kristal guda tare da wannan crystal. lokaci a matsayin substrate.
(2) Ana samun ci gaban epitaxial mai girma ta hanyar gabatar da tushen siliki mai ɗauke da chlorine. A cikin tsarin shigar da tururin sinadarai na al'ada na SiC, silane da propane (ko ethylene) sune manyan tushen haɓaka. A cikin aiwatar da haɓaka ƙimar haɓaka ta haɓaka ƙimar tushen haɓakar haɓaka, yayin da ma'aunin ɓangaren ɓangaren siliki ke ci gaba da ƙaruwa, yana da sauƙi don ƙirƙirar gungu na silicon ta hanyar haɓakar lokaci mai kama da iskar gas, wanda ke rage ƙimar amfani da mahimmanci. tushen siliki. Samuwar gungu na silicon yana iyakance haɓaka haɓakar haɓakar epitaxial sosai. A lokaci guda, gungu na siliki na iya dagula haɓakar haɓakar matakin da haifar da lahani na tsakiya. Don guje wa ƙawancen lokaci na iskar gas mai kama da ƙara haɓakar haɓakar epitaxial, ƙaddamar da tushen siliki na tushen chlorine a halin yanzu shine babbar hanyar haɓaka ƙimar haɓakar epitaxial na 4H-SiC.
1.2 200 mm (8-inch) SiC epitaxial kayan aiki da yanayin tsari
Gwaje-gwajen da aka bayyana a cikin wannan takarda duk an gudanar da su ne a kan katangar zafi mai tsayin 150/200 (6/8-inch) mai dacewa da katanga mai zafi na SiC kayan aikin epitaxial wanda cibiyar 48th Institute of China Electronics Technology Group Corporation ta kirkira. Tanderun epitaxial yana goyan bayan loda wafer cikakke ta atomatik da saukewa. Hoto na 1 shine zane mai zane na tsarin ciki na ɗakin amsawa na kayan aikin epitaxial. Kamar yadda aka nuna a cikin Hoto na 1, bangon waje na ɗakin amsawa shine kararrawa ma'adini tare da mai sanyaya ruwa mai sanyaya, kuma cikin kararrawa wani ɗakin amsawa mai zafi ne mai zafi, wanda ya hada da zafin jiki na thermal carbon feel, high-tsarki. Kogon graphite na musamman, tushe mai jujjuyawar iskar gas mai graphite, da sauransu. Gabaɗayan kararwar ma'adini an lulluɓe shi da coil induction cylindrical, kuma ɗakin amsawa a cikin kararrawa yana mai zafi ta hanyar samar da wutar lantarki mai matsakaici-mita. Kamar yadda aka nuna a cikin Hoto 1 (b), iskar gas mai ɗaukar kaya, iskar gas, da iskar gas ɗin doping duk suna gudana ta saman wafer a cikin madaidaicin laminar daga sama na ɗakin amsawa zuwa ƙasan ɗakin amsawa kuma ana fitar da su daga wutsiya. gas karshen. Don tabbatar da daidaito a cikin wafer, wafer ɗin da aka ɗauka ta hanyar iska mai iyo tushe koyaushe yana juyawa yayin aiwatarwa.
Matsakaicin da aka yi amfani da shi a cikin gwaji shine 150 mm na kasuwanci, 200 mm (inci 6, 8 inci) <1120> shugabanci 4 ° kashe-kusurwar gudanarwa n-nau'in 4H-SiC mai fuska biyu mai goge SiC substrate wanda Shanxi Shuoke Crystal ya samar. Ana amfani da Trichlorosilane (SiHCl3, TCS) da ethylene (C2H4) azaman babban tushen haɓakawa a cikin gwajin tsari, waɗanda TCS da C2H4 ana amfani da su azaman tushen silicon da tushen carbon bi da bi, ana amfani da nitrogen mai tsabta (N2) azaman n- nau'in tushen doping, kuma hydrogen (H2) ana amfani dashi azaman dilution gas da iskar gas. Matsakaicin zafin jiki na tsarin epitaxial shine 1 600 ~ 1 660 ℃, matsin lamba shine 8 × 103 ~ 12 × 103 Pa, kuma H2 mai ɗaukar iskar gas shine 100 ~ 140 L / min.
1.3 Gwajin wafer na Epitaxial da halayyar
Fourier infrared spectrometer (masu sana'a Thermalfisher, model iS50) da mercury bincike maida hankali tester (kayan aiki Semilab, model 530L) aka yi amfani da su nuna ma'ana da rarraba epitaxial Layer kauri da kuma doping maida hankali; An ƙaddara kauri da doping na kowane ma'ana a cikin Layer epitaxial ta hanyar ɗaukar maki tare da layin diamita da ke tsaka da layi na yau da kullum na babban mahimmanci a 45 ° a tsakiyar wafer tare da cire 5 mm gefen. Don wafer na 150 mm, an ɗauki maki 9 tare da layin diamita guda ɗaya (diamita biyu sun kasance daidai da juna), kuma don wafer 200 mm, an ɗauki maki 21, kamar yadda aka nuna a cikin Hoto 2. Na'urar microscope ta atomatik (masana'anta kayan aiki). An yi amfani da Bruker, samfurin Dimension Icon) don zaɓar wuraren 30 μm × 30 μm a cikin yankin tsakiya da kuma gefen gefen (5 mm gefen cire) na wafer na epitaxial don gwada yanayin da ake ciki na epitaxial Layer; an auna lahani na epitaxial Layer ta amfani da ma'auni mai lahani (masu sana'a na China Electronics Hoton 3D yana da alamar firikwensin radar (samfurin Mars 4410 pro) daga Kefenghua.
Lokacin aikawa: Satumba-04-2024