Isiphene esinxantathu
Iziphene ezinxantathu zezona ziphene zibulalayo kakhulu kwiileya ze-epitaxial ze-SiC. Inani elikhulu leengxelo zoncwadi libonise ukuba ukwakheka kweziphene ezinxantathu kunxulumene nemo yekristale ye-3C. Nangona kunjalo, ngenxa yeendlela ezahlukeneyo zokukhula, imo yeziphene ezininzi ezinxantathu kumphezulu weleya ye-epitaxial yahlukile kakhulu. Ingahlulwahlulwa ibe ziintlobo ezilandelayo:
(1) Kukho iziphene ezinxantathu kunye namasuntswana amakhulu phezulu
Olu hlobo lwesiphene esingunxantathu lunesuntswana elikhulu elingqukuva phezulu, elinokubangelwa zizinto eziwayo ngexesha lenkqubo yokukhula. Indawo encinci engunxantathu enomphezulu orhabaxa inokubonwa ezantsi ukusuka kule vertex. Oku kungenxa yokuba ngexesha lenkqubo ye-epitaxial, iileya ezimbini ezahlukeneyo ze-3C-SiC zenziwa ngokulandelelana kwindawo engunxantathu, apho umaleko wokuqala uxutywe kwi-interface kwaye ukhula ngokuhamba kwenyathelo le-4H-SiC. Njengoko ubukhulu bomaleko we-epitaxial bukhula, umaleko wesibini we-3C polytype nucleates kwaye ukhula kwimingxuma emincinci engunxantathu, kodwa inyathelo lokukhula le-4H aligubungeli ngokupheleleyo indawo ye-3C polytype, okwenza indawo ye-groove enomfanekiso we-V ye-3C-SiC isabonakala ngokucacileyo.
(2) Kukho amasuntswana amancinci phezulu kunye neziphene ezinxantathu ezinomphezulu orhabaxa
Amasuntswana akwii-vertices zolu hlobo lwesiphene esinxantathu mancinci kakhulu, njengoko kubonisiwe kuMfanekiso 4.2. Kwaye uninzi lwendawo enxantathu igutyungelwe yi-step flow ye-4H-SiC, oko kukuthi, lonke umaleko we-3C-SiC ufakwe ngokupheleleyo phantsi komaleko we-4H-SiC. Kuphela ngamanyathelo okukhula e-4H-SiC anokubonwa kumphezulu wesiphene esinxantathu, kodwa la manyathelo makhulu kakhulu kunamanyathelo okukhula kwekristale ye-4H eqhelekileyo.
(3) Iziphene ezinxantathu ezinomphezulu ogudileyo
Olu hlobo lwesiphene esingunxantathu lunemofoloji yomphezulu ogudileyo, njengoko kubonisiwe kuMfanekiso 4.3. Kwiimpazamo ezinjalo ezingunxantathu, umaleko we-3C-SiC ugutyungelwe yi-step flow ye-4H-SiC, kwaye imo yekristale ye-4H kumphezulu ikhula ibe mhle kwaye ithambile.
Iziphene zomngxuma we-Epitaxial
Iipithi ze-Epitaxial (iiPithi) zezinye zeziphene eziqhelekileyo zesimo somphezulu, kwaye imo yazo eqhelekileyo yomphezulu kunye noyilo lwesakhiwo ziboniswe kuMfanekiso 4.4. Indawo yeipithi zokubola ze-threading dislocation (TD) ezibonwe emva kokugrumba kwe-KOH ngasemva kwesixhobo inokuhambelana okucacileyo nendawo yeipithi ze-epitaxial ngaphambi kokulungiswa kwesixhobo, okubonisa ukuba ukwakheka kweziphene zepithi ze-epitaxial kunxulumene nokukhutshelwa kwentambo.
iziphene zekherothi
Iziphene zekaroti zizinto eziqhelekileyo ezibangela isiphene kumphezulu kwiileya ze-4H-SiC epitaxial, kwaye imo yazo eqhelekileyo iboniswe kuMfanekiso 4.5. Isiphene sekaroti kuthiwa senziwe kukudibana kweziphene ze-Franconian kunye ne-prismatic stacking ezikwi-basal plane ezidityaniswe yi-step-like dislocations. Kukwaxelwe ukuba ukwakheka kweziphene zekaroti kunxulumene ne-TSD kwi-substrate. UTsuchida H. et al. bafumanise ukuba ubuninzi beziphene zekaroti kumaleko we-epitaxial buhambelana nobunzima be-TSD kwi-substrate. Kwaye ngokuthelekisa imifanekiso yemo yomhlaba ngaphambi nasemva kokukhula kwe-epitaxial, zonke iziphene zekaroti ezibonisiweyo zinokufunyanwa zihambelana ne-TSD kwi-substrate. UWu H. et al. basebenzise uvavanyo lwe-Raman scattering characterization ukufumanisa ukuba iziphene zekaroti azinalo uhlobo lwekristale ye-3C, kodwa kuphela i-polytype ye-4H-SiC.
Isiphumo seziphene ezinxantathu kwiimpawu zesixhobo seMOSFET
Umfanekiso 4.7 yi-histogram yokwabiwa kweenkcukacha-manani zeempawu ezintlanu zesixhobo esineziphene ezinxantathu. Umgca oluhlaza okwesibhakabhaka onamachaphaza ngumgca owahlulayo wokonakala kweempawu zesixhobo, kwaye umgca obomvu onamachaphaza ngumgca owahlulayo wokonakala kwesixhobo. Ukusilela kwesixhobo, iziphene ezinxantathu zinempembelelo enkulu, kwaye izinga lokungaphumeleli lingaphezulu kwama-93%. Oku kubangelwa ikakhulu yimpembelelo yeziphene ezinxantathu kwiimpawu zokuvuza ezingasemva kwezixhobo. Ukufikelela kwi-93% yezixhobo ezineziphene ezinxantathu zinyuse kakhulu ukuvuza okungasemva. Ukongeza, iziphene ezinxantathu nazo zinempembelelo enkulu kwiimpawu zokuvuza kwesango, ngesantya sokubola sama-60%. Njengoko kubonisiwe kwiTheyibhile 4.2, ngokonakala kwe-threshold voltage kunye nokubola kweempawu ze-diode yomzimba, impembelelo yeziphene ezinxantathu incinci, kwaye iinxalenye zokubola ziyi-26% kunye ne-33% ngokulandelelana. Ngokuphathelele ukubangela ukwanda kokuxhathisa, impembelelo yeziphene ezinxantathu ibuthathaka, kwaye umlinganiselo wokubola umalunga nama-33%.
Isiphumo seziphene ze-epitaxial pit kwiimpawu zesixhobo se-MOSFET
Umfanekiso 4.8 yi-histogram yokwabiwa kweenkcukacha-manani zeempawu ezintlanu zesixhobo esineziphene zepit epitaxial. Umgca oluhlaza okwesibhakabhaka onamachaphaza ngumgca owahlulayo wokonakala kweempawu zesixhobo, kwaye umgca obomvu onamachaphaza ngumgca owahlulayo wokusilela kwesixhobo. Kuyabonakala koku ukuba inani lezixhobo ezineziphene zepit epitaxial kwisampulu ye-SiC MOSFET lilingana nenani lezixhobo ezineziphene ezinxantathu. Impembelelo yeziphene zepit epitaxial kwiimpawu zesixhobo yahlukile kweyokukhubazeka okunxantathu. Ngokuphathelele ukungaphumeleli kwesixhobo, izinga lokungaphumeleli kwezixhobo ezineziphene zepit epitaxial liyi-47% kuphela. Xa kuthelekiswa neziphene ezinxantathu, impembelelo yeziphene zepit epitaxial kwiimpawu zokuvuza okungasemva kunye neempawu zokuvuza kwesango lesixhobo ibuthathaka kakhulu, kunye nomlinganiselo wokubola we-53% kunye ne-38% ngokulandelelana, njengoko kubonisiwe kwiTheyibhile 4.3. Kwelinye icala, impembelelo yeziphene zepit epitaxial kwiimpawu ze-threshold voltage, iimpawu zokuqhuba i-diode yomzimba kunye nokuxhathisa kwayo kukhulu kunezo zeziphene ezinxantathu, kunye nomlinganiselo wokubola ofikelela kwi-38%.
Ngokubanzi, iziphene ezimbini zemo, ezizezi-triangles kunye ne-epitaxial pits, zinempembelelo enkulu ekusileleni nasekuwohlokeni kwezixhobo ze-SiC MOSFET. Ubukho beziphene ezi-triangular zezona zibulalayo, kunye nezinga lokungaphumeleli elifikelela kwi-93%, ikakhulu ezibonakala njengokwanda okukhulu kokuvuza okungasemva kwesixhobo. Izixhobo ezineziphene ze-epitaxial pit zazinezinga lokungaphumeleli eliphantsi le-47%. Nangona kunjalo, iziphene ze-epitaxial pit zinempembelelo enkulu kwi-threshold voltage yesixhobo, iimpawu zokuqhuba i-diode yomzimba kunye nokuxhathisa kwayo kuneziphene ezi-triangular.
Ixesha leposi: Epreli-16-2024