2 Iziphumo zovavanyo kunye nengxoxo
2.1Umaleko we-Epitaxialubukhulu kunye nokufana
Ubungqingqwa be-Epitaxial layer, ugxininiso lwe-doping kunye nokufana ngomnye wezalathi ezingundoqo zokugweba umgangatho we-epitaxial wafers. Ubukhulu obulawulekayo ngokuchanekileyo, ugxininiso lwe-doping kunye nokufana phakathi kwe-wafer ngundoqo ekuqinisekiseni ukusebenza kunye nokungaguquguqukiIzixhobo zamandla eSiC, kunye nobukhulu be-epitaxial layer kunye nokufana kwe-doping concentration nazo ziziseko ezibalulekileyo zokulinganisa amandla enkqubo yezixhobo ze-epitaxial.
Umzobo wesi-3 ubonisa ukufana kobukhulu kunye nokusabalalisa ijika le-150 mm kunye ne-200 mmI-SiC epitaxial wafers. Inokubonwa kumzobo ukuba i-epitaxial layer thick distribution curve i-symmetrical malunga nombindi we-wafer. Ixesha lenkqubo ye-epitaxial ngama-600s, ubukhulu be-epitaxial layer ye-150mm ye-epitaxial wafer yi-10.89 um, kwaye ukufana kobunzima yi-1.05%. Ngokubala, izinga lokukhula kwe-epitaxial yi-65.3 um / h, eyona nqanaba eliqhelekileyo lenkqubo ye-epitaxial. Ngaphantsi kwexesha elifanayo lenkqubo ye-epitaxial, ubukhulu be-epitaxial layer ye-200 mm ye-epitaxial wafer yi-10.10 um, ubukhulu obufanayo bungaphakathi kwe-1.36%, kwaye izinga lokukhula ngokubanzi li-60.60 um / h, elingaphantsi kancinci kunokukhula kwe-epitaxial ye-150 mm. izinga. Oku kungenxa yokuba kukho ilahleko ecacileyo endleleni xa umthombo wesilicon kunye nomthombo wekhabhoni uphuma usuka phezulu kwegumbi lokusabela udlula kwindawo yesiwapha ukuya ezantsi kwegumbi lokusabela, kwaye indawo ye-wafer eyi-200 mm inkulu kune-150 mm. Irhasi ihamba kumphezulu we-200 mm wafer umgama omde, kwaye umthombo wegesi osetyenzisiweyo endleleni ungaphezulu. Ngaphantsi kwemeko yokuba i-wafer igcina ukujikeleza, ubukhulu becala le-epitaxial layer buncinci, ngoko izinga lokukhula lihamba kancinci. Ngokubanzi, ubukhulu obufanayo be-150 mm kunye ne-200 mm epitaxial wafers bugqwesileyo, kwaye inkqubo yobuchule besixhobo inokuhlangabezana neemfuno zezixhobo eziphezulu.
2.2 I-Epitaxial layer doping concentration kunye nokufana
Umzobo 4 ubonisa ukufana koxinaniso lwedoping kunye nokuhanjiswa kwegophe le-150 mm kunye ne-200 mm.I-SiC epitaxial wafers. Njengoko kunokubonwa kumzobo, ijiko losasazo loxinaniso kwi-wafer ye-epitaxial ine-symmetry ecacileyo xa kuthelekiswa nombindi we-wafer. I-doping concentration uniformity ye-150 mm kunye ne-200 mm epitaxial layers yi-2.80% kunye ne-2.66% ngokulandelanayo, enokulawulwa ngaphakathi kwe-3%, eyona nqanaba elihle kakhulu kwizixhobo ezifanayo zamazwe ngamazwe. Ijiko loxinaniso lwe-doping yomaleko we-epitaxial isasazwe kwimilo ethi "W" ecaleni kwecala ledayamitha, emiselwa ubukhulu becala yintsimi yokuhamba ethe tye eludongeni olushushu lwe-epitaxial furnace, ngenxa yokuba isalathiso sokuhamba komoya se-horizontal airflow epitaxial growth furnace ivela. isiphelo sokungena komoya (entla komlambo) kwaye uqukuqela uphuma kwisiphelo somlambo ngendlela yelaminar kumhlaba osicaba; ngenxa yokuba "indlela yokuncipha" izinga lomthombo wekhabhoni (C2H4) liphezulu kunelo lomthombo we-silicon (TCS), xa i-wafer ijikeleza, i-C / Si yokwenyani kumphezulu we-wafer iyancipha ngokuthe ngcembe ukusuka emphethweni ukuya. Iziko (umthombo wekhabhoni embindini ungaphantsi), ngokutsho "kwithiyori yesikhundla sokukhuphisana" ye-C kunye ne-N, i-doping concentration kumbindi we-wafer iyancipha ngokuthe ngcembe ukuya emphethweni, ukuze ufumane ugxininiso olubalaseleyo. ukufana, i-edge N2 yongezwa njengembuyekezo ngexesha lenkqubo ye-epitaxial ukucotha ukuhla koxinzelelo lwe-doping ukusuka embindini ukuya emphethweni, ukwenzela ukuba ijika lokugqibela logxininiso lwe-doping lubonise "W" imilo.
2.3 Iziphene ze-Epitaxial layer
Ukongeza kubunzima kunye noxinzelelo lwe-doping, inqanaba lolawulo lwesiphene se-epitaxial likwayiparameter ephambili yokulinganisa umgangatho we-epitaxial wafers kunye nesalathisi esibalulekileyo sobuchule benkqubo yezixhobo ze-epitaxial. Nangona i-SBD kunye ne-MOSFET zineemfuno ezahlukeneyo zeziphene, iziphene ezicace ngakumbi ze-morphology yomphezulu ezifana neziphene zokuwa, iziphene ezinxantathu, iziphene zeminqathe, iziphene ze-comet, njl. Ukungaphumeleli kweetshiphusi eziqulethe ezi ziphene kuphezulu, ngoko ke ukulawula inani leziphene zokubulala kubaluleke kakhulu ekuphuculeni isivuno se-chip kunye nokunciphisa iindleko. Umzobo we-5 ubonisa ukuhanjiswa kweziphene zokubulala i-150 mm kunye ne-200 mm ye-SiC epitaxial wafers. Ngaphantsi kwemeko yokuba akukho kungalingani okucacileyo kwi-C / Si ratio, i-carrot defects kunye ne-comet defects inokupheliswa ngokusisiseko, ngelixa iziphene zokulahla kunye neziphene ezinxantathu zihambelana nokulawula ukucoceka ngexesha lokusebenza kwezixhobo ze-epitaxial, izinga lokungcola kwegraphite. iinxalenye kwigumbi lokuphendula, kunye nomgangatho we-substrate. Ukususela kwiThebhile 2, kunokubonwa ukuba i-defect defect density ye-150 mm kunye ne-200 mm epitaxial wafers ingalawulwa ngaphakathi kwe-0.3 particles / cm2, eyona nqanaba elihle kakhulu lohlobo olufanayo lwezixhobo. Inqanaba lokulawula uxinaniso olubulalayo lwe-150 mm epitaxial wafer lungcono kune-200 mm epitaxial wafer. Oku kungenxa yokuba inkqubo yokulungiselela i-substrate ye-150 mm ikhulile ngaphezu kwe-200 mm, umgangatho we-substrate ungcono, kunye nenqanaba lokulawula ukungcola kwe-150 mm yegumbi lokuphendula i-graphite lingcono.
2.4 Uburhabaxa bomphezulu we-Epitaxial wafer
Umzobo we-6 ubonisa imifanekiso ye-AFM yobuso be-150 mm kunye ne-200 mm ye-SiC epitaxial wafers. Inokubonwa kumfanekiso ukuba ingcambu yomphezulu ithetha uburhabaxa obusikwere Ra we-150 mm kunye ne-200 mm epitaxial wafers yi-0.129 nm kunye ne-0.113 nm ngokulandelelana, kunye nomphezulu we-epitaxial layer igudileyo ngaphandle kwesiganeko esicacileyo sokuhlanganiswa kwe-macro-step. Le nto ibonisa ukuba ukukhula kwe-epitaxial layer isoloko igcina imo yokukhula kwenyathelo ngexesha lenkqubo yonke ye-epitaxial, kwaye akukho nyathelo lokuhlanganisa okwenzekayo. Ingabonwa ukuba ngokusebenzisa inkqubo yokukhula kwe-epitaxial ephuculweyo, i-epitaxial layers egudileyo inokufumaneka kwi-150 mm kunye ne-200 mm ye-angle ephantsi.
3 Isiphelo
I-150 mm kunye ne-200 mm 4H-SiC i-epitaxial wafers e-homogeneous epitaxial wafers yalungiswa ngempumelelo kwii-substrates zasekhaya zisebenzisa i-self-developed 200 mm SiC izixhobo zokukhula kwe-epitaxial, kunye nenkqubo ye-epitaxial ye-homogeneous efanelekileyo kwi-150 mm kunye ne-200 mm yaphuhliswa. Izinga lokukhula kwe-epitaxial linokuba likhulu kune-60 μm / h. Ngelixa udibana nemfuno ye-epitaxy enesantya esiphezulu, umgangatho we-epitaxial wafer ugqwesile. Ubukhulu obufanayo be-150 mm kunye ne-200 mm ye-epitaxial wafers ye-SiC inokulawulwa ngaphakathi kwe-1.5%, i-concentration uniformity ingaphantsi kwe-3%, ukuxinwa kwesiphako esibulalayo kungaphantsi kwe-0.3 particles / cm2, kunye ne-epitaxial surface roughness root mean square Ra ingaphantsi kwe-0.15 nm. Iimpawu eziphambili zenkqubo ye-epitaxial wafers zikwizinga eliphezulu kwishishini.
Umthombo: Izixhobo eziZodwa kwiShishini loMbane
Umbhali: Xie Tianle, Li Ping, Yang Yu, Gong Xiaoliang, Ba Sai, Chen Guoqin, Wan Shengqiang
(48th Institute Research of China Electronics Technology Group Corporation, Changsha, Hunan 410111)
Ixesha lokuposa: Sep-04-2024