Ubuchwepheshe obuyinhloko bokukhula kwe-I-SiC epitaxialIzinto zokwakha okokuqala ubuchwepheshe bokulawula amaphutha, ikakhulukazi ubuchwepheshe bokulawula amaphutha obuvame ukwehluleka kwedivayisi noma ukuwohloka kokuthembeka. Ucwaningo lwendlela yokusebenza kwamaphutha e-substrate enwebeka kungqimba lwe-epitaxial ngesikhathi senqubo yokukhula kwe-epitaxial, imithetho yokudlulisa nokuguqula amaphutha esixhumini esiphakathi kwengqimba ye-substrate ne-epitaxial, kanye nendlela yokwakheka kwamaphutha e-nucleation kuyisisekelo sokucacisa ubudlelwano phakathi kwamaphutha e-substrate namaphutha esakhiwo se-epitaxial, okungaqondisa ngempumelelo ukuhlolwa kwe-substrate kanye nokwenza ngcono inqubo ye-epitaxial.
Amaphutha kaizendlalelo ze-epitaxial ze-silicon carbidezihlukaniswe kakhulu ngezigaba ezimbili: amaphutha ekristalu kanye namaphutha okwakheka kwendawo. Amaphutha ekristalu, okuhlanganisa amaphutha amaphoyinti, ukuhlukana kwezikulufo, amaphutha e-microtubule, ukuhlukana komphetho, njll., ikakhulukazi avela kumaphutha kuma-substrate e-SiC futhi asakazeka kungqimba lwe-epitaxial. Amaphutha okwakheka kwendawo angabonakala ngqo ngeso lenyama kusetshenziswa i-microscope futhi abe nezici ezijwayelekile zokwakheka kwendawo. Amaphutha okwakheka kwendawo ahlanganisa kakhulu: Ukuklwebheka, isici esingunxantathu, isici se-carrot, i-Downfall, kanye ne-Particle, njengoba kuboniswe kuMfanekiso 4. Ngesikhathi senqubo ye-epitaxial, izinhlayiya zangaphandle, amaphutha e-substrate, umonakalo wobuso, kanye nokuphambuka kwenqubo ye-epitaxial konke kungathinta imodi yokukhula kokugeleza kwesinyathelo sendawo, okuholela emaphutheni okwakheka kwendawo.
Ithebula 1. Izimbangela zokwakheka kwamaphutha avamile e-matrix kanye namaphutha okwakheka kobuso ezingqimbeni ze-SiC epitaxial
Amaphutha amaphuzu
Amaphutha amaphoyinti akhiwa yizikhala noma izikhala endaweni eyodwa ye-lattice noma ezindaweni eziningana ze-lattice, futhi azinazo izandiso zesikhala. Amaphutha amaphoyinti angenzeka kuyo yonke inqubo yokukhiqiza, ikakhulukazi ekufakweni kwe-ion. Kodwa-ke, kunzima ukuwabona, futhi ubudlelwano phakathi kokuguqulwa kwamaphutha amaphoyinti nezinye iziphambeko nakho kuyinkimbinkimbi kakhulu.
Amapayipi Amancane (MP)
Ama-micropipe ayizikulufo ezingenalutho ezisakazeka eduze kwe-growth axis, nge-Burgers vector <0001>. Ububanzi bama-microtube busukela engxenyeni ye-micron kuya kumashumi ama-micron. Ama-Microtube abonisa izici ezinkulu ezifana nomgodi ebusweni bama-SiC wafers. Ngokuvamile, ubuningi bama-microtube bungaba ngu-0.1 ~ 1cm-2 futhi buyaqhubeka nokwehla ekuqaphelweni kwekhwalithi yokukhiqizwa kwe-wafer yezentengiselwano.
Ukuhlukaniswa kwezikulufo (TSD) kanye nokuhlukaniswa komphetho (TED)
Ukungalungi ku-SiC kuwumthombo oyinhloko wokuwohloka nokwehluleka kwedivayisi. Kokubili ukungalungi kwezikulufo (TSD) kanye nokungalungi konqenqema (TED) kuhamba nge-growth axis, kanye nama-Burger vectors angu-<0001> kanye no-1/3<11–20>, ngokulandelana.
Kokubili ukuhlukaniswa kwezikulufo (TSD) kanye nokuhlukaniswa konqenqema (TED) kunganwebeka kusuka ku-substrate kuye endaweni ye-wafer futhi kulethe izici zobuso ezincane ezifana nemigodi (Isithombe 4b). Ngokuvamile, ubukhulu bokuhlukaniswa konqenqema cishe buphindwe kayishumi kunokwehlukaniswa kwezikulufo. Ukuhlukaniswa kwezikulufo okunwetshiwe, okungukuthi, okunwebeka kusuka ku-substrate kuya ku-epilayer, nakho kungaguquka kube ezinye iziphambeko futhi kusakazeke ku-axis yokukhula. Ngesikhathi sokusetshenziswa kwe-screw, i-screw dislocation ingase ishintshe ibe ezinye iziphambeko futhi isakazeke ku-axis yokukhula.I-SiC epitaxialukukhula, ukuhlukaniswa kwezikulufo kuguqulwa kube amaphutha okuhlanganisa (SF) noma amaphutha ekherothi, kuyilapho ukuhlukaniswa komphetho kuma-epilayers kuboniswa kuguqulwa kusuka ekuhlukanisweni kwendiza yesisekelo (ama-BPD) okuzuzwe njengefa kusukela ku-substrate ngesikhathi sokukhula kwe-epitaxial.
Ukuhlukaniswa kwendiza okuyisisekelo (i-BPD)
Itholakala endaweni engezansi ye-SiC, ene-vector ye-Burgers engu-1/3 <11–20>. Ama-BPD awavamile ukuvela ebusweni be-SiC wafers. Ngokuvamile agxile endaweni engaphansi enobukhulu obungu-1500 cm-2, kuyilapho ubukhulu bawo ku-epilayer bungu-10 cm-2 kuphela. Ukutholwa kwama-BPD kusetshenziswa i-photoluminescence (PL) kukhombisa izici eziqondile, njengoba kuboniswe kuMfanekiso 4c. NgesikhathiI-SiC epitaxialukukhula, ama-BPD anwetshiwe angaguqulwa abe amaphutha okuhlanganisa (SF) noma ama-edge dislocations (TED).
Amaphutha okubeka izinto (ama-SF)
Amaphutha ochungechungeni lokuhlanganisa lwendiza ye-basal ye-SiC. Amaphutha okuhlanganisa angavela kungqimba ye-epitaxial ngokuzuza ama-SF ku-substrate, noma ahlotshaniswe nokwandiswa nokuguqulwa kokuhlukanisa kwendiza ye-basal (BPDs) kanye nokuhlukanisa izikulufo zokuxhuma (TSDs). Ngokuvamile, ubukhulu be-SF bungaphansi kuka-1 cm-2, futhi bubonisa isici esingunxantathu uma kutholwa kusetshenziswa i-PL, njengoba kuboniswe kuMfanekiso 4e. Kodwa-ke, izinhlobo ezahlukene zamaphutha okuhlanganisa zingakheka ku-SiC, njengohlobo lwe-Shockley kanye nohlobo lwe-Frank, ngoba ngisho nokuphazamiseka kwamandla okuhlanganisa phakathi kwezindiza kungaholela ekungalingani okukhulu ochungechungeni lokuhlanganisa.
Ukuwa
Iphutha lokuwa livela kakhulu ekuweni kwezinhlayiya ezindongeni eziphezulu neziseceleni zegumbi lokusabela ngesikhathi senqubo yokukhula, okungathuthukiswa ngokwenza ngcono inqubo yokugcinwa kwe-graphite yegumbi lokusabela ngezikhathi ezithile.
Iphutha elingunxantathu
Kuyi-3C-SiC polytype efakwayo efinyelela ebusweni be-SiC epilayer eceleni kwendlela ye-basal plane, njengoba kuboniswe ku-Figure 4g. Ingadalwa yizinhlayiya eziwela phezu kwe-SiC epilayer ngesikhathi sokukhula kwe-epitaxial. Izinhlayiya zifakwa ku-epilayer futhi ziphazamisa inqubo yokukhula, okuholela ekufakweni kwe-3C-SiC polytype, okubonisa izici zobuso obunxantathu obucijile nezinhlayiya ezitholakala emaphethelweni esifunda esingunxantathu. Izifundo eziningi ziphinde zathi imvelaphi yokufakwa kwe-polytype inclusions ibangelwa ukuklwebheka kobuso, amapayipi amancane, kanye nemingcele engafanele yenqubo yokukhula.
Iphutha likakaroti
I-carrot defect iyi-stacking fault complex enezinhlangothi ezimbili ezitholakala ku-TSD kanye ne-SF basal crystal planes, ephela ngokuhlukana kohlobo lwe-Frank, futhi ubukhulu be-carrot defect buhlobene ne-prismatic stacking fault. Inhlanganisela yalezi zici yakha isimo sobuso be-carrot defect, esibukeka njengesimo se-carrot esinobukhulu obungaphansi kuka-1 cm-2, njengoba kuboniswe kuMfanekiso 4f. I-carrot defects yakheka kalula ekupholiseni imihuzuko, ama-TSD, noma amaphutha e-substrate.
Ukuklwebheka
Ukuklwebheka kuwumonakalo womshini ebusweni bama-wafer e-SiC akhiwe ngesikhathi senqubo yokukhiqiza, njengoba kuboniswe kuMfanekiso 4h. Ukuklwebheka ku-substrate ye-SiC kungaphazamisa ukukhula kwe-epilayer, kukhiqize umugqa wokuhlukana okuphezulu ngaphakathi kwe-epilayer, noma ukuklwebheka kungaba yisisekelo sokwakheka kwamaphutha e-carrot. Ngakho-ke, kubalulekile ukupholisha kahle ama-wafer e-SiC ngoba lokhu klwebheka kungaba nomthelela omkhulu ekusebenzeni kwedivayisi uma kuvela endaweni esebenzayo yedivayisi.
Ezinye izinkinga zesimo sobuso
I-Step bunching iyisici sobuso esakheka ngesikhathi senqubo yokukhula kwe-SiC epitaxial, ekhiqiza onxantathu abangabonakali noma izici ze-trapezoidal ebusweni be-epilayer ye-SiC. Kunezinye izinkinga eziningi zobuso, njengemigodi yobuso, amaqhubu namabala. Lezi ziphutha zivame ukubangelwa izinqubo zokukhula ezingalungiswanga kanye nokususwa okungaphelele komonakalo wokupholisha, okuthinta kabi ukusebenza kwedivayisi.
Isikhathi sokuthunyelwe: Juni-05-2024