Ama-semiconductors e-Wide bandgap (WBG) amelwe i-silicon carbide (SiC) ne-gallium nitride (GaN) athole ukunakwa okusabalele. Abantu balindele okukhulu ngamathemba okusetshenziswa kwe-silicon carbide ezimotweni zikagesi namagridi kagesi, kanye nethemba lokusetshenziswa kwe-gallium nitride ekushajweni okusheshayo. Eminyakeni yamuva nje, ucwaningo lwe-Ga2O3, i-AlN nezinto zedayimane zenze inqubekelaphambili enkulu, okwenza izinto ezisetshenziswayo ze-ultra-wide bandgap semiconductor zibe ukugxila kakhulu. Phakathi kwazo, i-gallium oxide (Ga2O3) iyimpahla evelayo ye-ultra-wide-wide-bandgap semiconductor enegebe lebhande elingu-4.8 eV, amandla enkambu yokwehlukana okucatshangelwayo acishe abe ngu-8 MV cm-1, isivinini sokugcwala esingaba ngu-2E7cm s-1, kanye nekhwalithi ephezulu ye-Baliga engu-3000, ithola ukunakwa okusabalele emkhakheni wamandla kagesi aphezulu kanye ne-high frequency power electronics.
1. Izici ze-Gallium oxide ezibonakalayo
I-Ga2O3 inegebe elikhulu lebhendi (i-4.8 eV), kulindeleke ukuthi izuze kokubili amandla kagesi aphezulu namandla amakhulu, futhi ingaba nethuba lokuguquguquka kwamandla kagesi aphezulu ekumelaneni okuphansi uma kuqhathaniswa, okuwenza agxile ocwaningweni lwamanje. Ngaphezu kwalokho, i-Ga2O3 ayigcini nje ngokuba nezinto ezinhle kakhulu zezinto ezibonakalayo, kodwa futhi inikeza ubuchwepheshe obuhlukahlukene obulungiseka kalula be-n-type doping, kanye nokukhula kwe-substrate okungabizi kakhulu kanye nobuchwepheshe be-epitaxy. Kuze kube manje, kutholwe izigaba zekristalu ezinhlanu ezihlukene ku-Ga2O3, okuhlanganisa i-corundum (α), i-monoclinic (β), i-spinel enesici (γ), i-cubic (δ) nezigaba ze-orthorhombic (ɛ). Ukuqina kwe-Thermodynamic, ngokulandelana, γ, δ, α, ɛ, kanye no-β. Kuyaphawuleka ukuthi i-monoclinic β-Ga2O3 iyona ezinzile kakhulu, ikakhulukazi emazingeni okushisa aphakeme, kuyilapho ezinye izigaba zikwazi ukumetastable ngaphezu kwezinga lokushisa legumbi futhi zivame ukuguquka zibe yisigaba sika-β ngaphansi kwezimo ezithile zokushisa. Ngakho-ke, ukuthuthukiswa kwamadivayisi asekelwe ku-β-Ga2O3 sekugxilwe kakhulu emkhakheni we-electronics yamandla eminyakeni yamuva.
Ithebula 1 Ukuqhathaniswa kwamanye amapharamitha we-semiconductor
Isakhiwo sekristalu se-monoclinicβ-Ga2O3 siboniswa kuThebula 1. Imingcele yayo ye-lattice ihlanganisa a = 12.21 Å, b = 3.04 Å, c = 5.8 Å, futhi β = 103.8 °. Iyunithi yeseli iqukethe ama-athomu e-Ga(I) anokuxhumana kwe-tetrahedral esontekile kanye nama-athomu e-Ga(II) anokuxhumana kwe-octahedral. Kunezinhlelo ezintathu ezihlukene zama-athomu omoya-mpilo kuhlelo “lwe-cubic esontiwe”, okuhlanganisa ama-athomu amabili adidiyelwe ngonxantathu O(I) kanye no-O(II) kanye ne-athomu eyodwa ye-O(III) ehlanganiswe nge-tetrahedral. Ukuhlanganiswa kwalezi zinhlobo ezimbili zokuxhumanisa kwe-athomu kuholela ku-anisotropy ye-β-Ga2O3 enezakhiwo ezikhethekile ku-physics, ukugqwala kwamakhemikhali, i-optics kanye ne-electronics.
Umfanekiso 1 Umdwebo wesakhiwo se-monoclinic β-Ga2O3 crystal
Ngokombono wethiyori yebhendi yamandla, inani eliphansi lebhendi yokuqhuba ye-β-Ga2O3 lisuselwa kusimo samandla esihambisana ne-4s0 hybrid orbit ye-Ga athomu. Umehluko wamandla phakathi kwenani eliphansi lebhendi yokuqhuba kanye neleveli yamandla e-vacuum (i-electron affinity energy) iyalinganiswa. ngi 4ev. Isisindo se-electron esebenzayo ye-β-Ga2O3 ikalwa njenge-0.28–0.33 me kanye nokuhamba kwayo kwe-elekthronikhi okuhle. Kodwa-ke, umkhawulo webhendi ye-valence ubonisa ijika le-Ek elingashoni eligobile eliphansi kakhulu nama-orbitals e-O2p enziwe ngokwendawo ngokuqinile, okuphakamisa ukuthi izimbobo zenziwe zasendaweni ngokujulile. Lezi zici zibeka inselele enkulu yokuthola i-p-type doping ku-β-Ga2O3. Ngisho noma i-P-type doping ingafinyelelwa, imbobo μ ihlala isezingeni eliphansi kakhulu. 2. Ukukhula kwenqwaba ye-gallium oxide ikristalu eyodwa Kuze kube manje, indlela yokukhula ye-β-Ga2O3 ngobuningi be-crystal substrate ngokuyinhloko iyindlela yokudonsa ngekristalu, njenge-Czochralski (CZ), indlela yokuphakela ifilimu elincanyana echazwe emaphethelweni (Edge -Defined film-fed , EFG), i-Bridgman (eqondile noma evundlile i-Bridgman, i-HB noma i-VB) kanye nobuchwepheshe bezoni entantayo (indawo entantayo, FZ). Phakathi kwazo zonke izindlela, i-Czochralski kanye nezindlela zokondla ifilimu emincane echazwe emaphethelweni kulindeleke ukuthi zibe izindlela ezithembisayo kakhulu zokukhiqiza ama-wafers amaningi e-β-Ga 2O3 esikhathini esizayo, njengoba zingakwazi ukufeza kanyekanye amavolumu amakhulu kanye nokuminyana kwesici esiphansi. Kuze kube manje, i-Novel Crystal Technology yase-Japan isithole i-matrix yokuhweba yokuncibilikisa ukukhula kwe-β-Ga2O3.
2.1 Indlela ye-Czochralski
Umgomo wendlela ye-Czochralski ukuthi ungqimba lwembewu lumbozwa kuqala, bese i-crystal eyodwa ikhishwa kancane kancane ekuncibilikeni. Indlela ye-Czochralski iya ngokuya ibaluleke kakhulu ku-β-Ga2O3 ngenxa yezindleko zayo eziphansi, amandla amakhulu osayizi, kanye nokukhula kwe-substrate yekhwalithi ephezulu yekristalu. Kodwa-ke, ngenxa yokucindezeleka okushisayo ngesikhathi sokukhula kwezinga lokushisa eliphezulu kwe-Ga2O3, ukuhwamuka kwekristalu eyodwa, izinto ezincibilikayo, nokulimala kwe-Ir crucible kuzokwenzeka. Lokhu kuwumphumela wobunzima bokuthola i-doping ephansi yohlobo lwe-n ku-Ga2O3. Ukwethula inani elifanele le-oxygen emkhathini wokukhula kungenye yezindlela zokuxazulula le nkinga. Ngokulungiselela, ikhwalithi ephezulu engu-2-inch β-Ga2O3 enobubanzi bamahhala be-electron obungu-10^16~10^19 cm-3 kanye nokuminyana kwama-electron okungu-160 cm2/Vs kukhuliswe ngempumelelo ngendlela ye-Czochralski.
Umfanekiso 2 Ikristalu eyodwa ye-β-Ga2O3 ekhuliswe indlela ye-Czochralski
2.2 Indlela yokuphakela ifilimu echazwe ngomphetho
Indlela yokuphakela ifilimu ezacile echazwe emaphethelweni ithathwa njengembangi ehamba phambili ekukhiqizeni ukuhweba kwezinto zekristalu eyodwa ye-Ga2O3 yendawo enkulu. Umgomo wale ndlela ukubeka ukuncibilika esikhunjeni nge-capillary slit, futhi ukuncibilika kukhuphukela esikhunjeni ngokusebenzisa isenzo se-capillary. Phezulu, ifilimu elincanyana liyabumba futhi lisakazeke kuzo zonke izinhlangothi kuyilapho liyengelwa ukuba licwebezeliswe yikristalu lembewu. Ukwengeza, imiphetho ye-mold top ingalawulwa ukuze kukhiqizwe amakristalu kuma-flakes, amashubhu, noma iyiphi i-geometry oyifunayo. Indlela yokudla yefilimu elincanyana echazwe emaphethelweni ye-Ga2O3 inikeza amazinga okukhula okusheshayo namadayimitha amakhulu. Umfanekiso wesi-3 ubonisa umdwebo wekristalu eyodwa ye-β-Ga2O3. Ukwengeza, ngokwesilinganiso sosayizi, ama-substrates angu-2-intshi angu-2 kanye ne-4-inch β-Ga2O3 anokucaca okuhle kakhulu nokufana aye athengiswa, kuyilapho i-substrate engu-6-intshi iboniswa ocwaningweni lokudayiswa kwesikhathi esizayo. Muva nje, izinto ezinkulu eziyindilinga zekristalu eyodwa nazo seziyatholakala ezinomumo othi (−201). Ukwengeza, indlela ye-β-Ga2O3 echazwe emaphethelweni yokudla ifilimu iphinde ikhuthaze ukusetshenziswa kwezakhi zensimbi eziguqukayo, okwenza ucwaningo nokulungiswa kwe-Ga2O3 kwenzeke.
Umfanekiso 3 β-Ga2O3 ikristalu eyodwa ekhuliswe ngendlela yefilimu echazwe emaphethelweni
2.3 Indlela yeBridgeman
Ngendlela ye-Bridgeman, amakristalu akhiwa ku-crucible ehamba kancane kancane nge-gradient yezinga lokushisa. Inqubo ingenziwa ngomumo ovundlile noma oqondile, ngokuvamile kusetshenziswa i-crucible ejikelezayo. Kuyaphawuleka ukuthi le ndlela ingase isebenzise imbewu yekristalu noma ingasebenzisi. Abaqhubi be-Traditional Bridgman abanakho ukubonwa okuqondile kwezinqubo zokuncibilika nokukhula kwekristalu futhi kufanele balawule amazinga okushisa ngokunemba okuphezulu. Indlela ye-Bridgman emile isetshenziswa kakhulu ekukhuleni kwe-β-Ga2O3 futhi yaziwa ngamandla ayo okukhula endaweni yomoya. Phakathi nenqubo yokukhula yendlela ye-Bridgman eqondile, ukulahlekelwa kwesisindo esiphelele sokuncibilika ne-crucible kugcinwa ngaphansi kwe-1%, okuvumela ukukhula kwamakristalu amakhulu e-β-Ga2O3 ngokulahleka okuncane.
Umfanekiso 4 Ikristalu eyodwa ye-β-Ga2O3 ekhuliswe indlela ye-Bridgeman
2.4 Indlela yendawo entantayo
Indlela yendawo entantayo ixazulula inkinga yokungcoliswa kwekristalu ngezinto ezibolekayo futhi inciphisa izindleko eziphakeme ezihambisana nezinsimbi ze-infrared ezimelana nokushisa okuphezulu. Phakathi nale nqubo yokukhula, ukuncibilika kungashiswa yisibani esikhundleni somthombo we-RF, ngaleyo ndlela kube lula izidingo zemishini yokukhula. Nakuba umumo nekhwalithi yekristalu ye-β-Ga2O3 ekhuliswe indlela yendawo entantayo ingakalungi, le ndlela ivula indlela ethembisayo yokukhula okuhlanzekile okuphezulu kwe-β-Ga2O3 ibe amakristalu angawodwa avumelana nesabelomali.
Umfanekiso 5 β-Ga2O3 ikristalu eyodwa ekhuliswe ngendlela yendawo entantayo.
Isikhathi sokuthumela: May-30-2024