Ua loaʻa i nā semiconductors wide bandgap (WBG) i hōʻike ʻia e ka silicon carbide (SiC) a me ka gallium nitride (GaN) ka nānā nui ʻia. Loaʻa i ka poʻe nā manaʻolana kiʻekiʻe no nā manaʻolana noi o ka silicon carbide i nā kaʻa uila a me nā pūnaewele mana, a me nā manaʻolana noi o ka gallium nitride i ka hoʻouka wikiwiki ʻana. I nā makahiki i hala iho nei, ua holomua nui ka noiʻi ʻana ma luna o Ga2O3, AlN a me nā mea daimana, e hoʻolilo ana i nā mea semiconductor bandgap ultra-wide i mea nui o ka nānā ʻana. I waena o lākou, ʻo ka gallium oxide (Ga2O3) kahi mea semiconductor ultra-wide-bandgap e kū mai ana me kahi band gap o 4.8 eV, kahi ikaika kahua haki koʻikoʻi theoretical ma kahi o 8 MV cm-1, kahi wikiwiki saturation ma kahi o 2E7cm s-1, a me kahi kumu maikaʻi Baliga kiʻekiʻe o 3000, e loaʻa ana ka nānā nui ʻia ma ke kahua o nā uila kiʻekiʻe a me nā uila mana alapine kiʻekiʻe.
1. Nā ʻano mea Gallium oxide
Loaʻa iā Ga2O3 kahi ākea band nui (4.8 eV), manaʻo ʻia e hoʻokō i nā voltage kūpaʻa kiʻekiʻe a me nā mana mana kiʻekiʻe, a hiki ke loaʻa ka hiki ke hoʻololi i ke voltage kiʻekiʻe ma ke kū'ē haʻahaʻa, e lilo ana lākou i kikowaena o ka noiʻi o kēia manawa. Eia kekahi, ʻaʻole wale ʻo Ga2O3 i nā waiwai mea maikaʻi loa, akā hāʻawi pū kekahi i nā ʻano ʻenehana doping n-type maʻalahi e hoʻololi, a me nā ʻenehana ulu substrate haʻahaʻa a me nā ʻenehana epitaxy. I kēia manawa, ua ʻike ʻia ʻelima mau ʻano kristal like ʻole ma Ga2O3, me nā ʻano corundum (α), monoclinic (β), spinel kīnā (γ), cubic (δ) a me orthorhombic (ɛ). ʻO nā kūpaʻa Thermodynamic, ma ke ʻano, γ, δ, α, ɛ, a me β. He mea kūpono ke hoʻomaopopo ʻana ʻo ka monoclinic β-Ga2O3 ka mea paʻa loa, ʻoi aku hoʻi ma nā mahana kiʻekiʻe, ʻoiai ʻo nā ʻano ʻē aʻe he metastable ma luna o ka mahana o ka lumi a ke ʻano nei e hoʻololi i ka ʻano β ma lalo o nā kūlana thermal kikoʻī. No laila, ua lilo ka hoʻomohala ʻana o nā polokalamu e pili ana i ka β-Ga2O3 i mea nui i ke kahua o nā mea uila mana i nā makahiki i hala iho nei.
Papa 1 Hoʻohālikelike o kekahi mau palena mea semiconductor
Ua hōʻike ʻia ke ʻano kristal o ka monoclinicβ-Ga2O3 ma ka Papa 1. ʻO kāna mau palena lattice e komo pū me a = 12.21 Å, b = 3.04 Å, c = 5.8 Å, a me β = 103.8°. Aia ka cell unit i nā ʻātoma Ga(I) me ka hoʻonohonoho tetrahedral twisted a me nā ʻātoma Ga(II) me ka hoʻonohonoho octahedral. Aia ʻekolu mau hoʻonohonoho like ʻole o nā ʻātoma oxygen i loko o ka "twisted cubic" array, me ʻelua mau ʻātoma O(I) a me O(II) i hoʻonohonoho ʻia ma ke ʻano triangular a me hoʻokahi ʻātoma O(III) i hoʻonohonoho ʻia ma ke ʻano tetrahedrally. ʻO ka hui pū ʻana o kēia mau ʻano ʻelua o ka hoʻonohonoho ʻātoma e alakaʻi ai i ka anisotropy o β-Ga2O3 me nā waiwai kūikawā i ka physics, ka pala kemika, nā optics a me nā mea uila.
Kiʻi 1 Kiʻikuhi hoʻonohonoho kiʻi o ke kristal monoclinic β-Ga2O3
Mai ka manaʻo o ke kumumanaʻo o ka hui ikehu, ua loaʻa ka waiwai liʻiliʻi loa o ka hui conduction o β-Ga2O3 mai ke kūlana ikehu e pili ana i ka orbit hybrid 4s0 o ka ʻātoma Ga. Ua ana ʻia ka ʻokoʻa ikehu ma waena o ka waiwai liʻiliʻi loa o ka hui conduction a me ka pae ikehu vacuum (energy affinity electron). ʻo 4 eV. Ua ana ʻia ka nui o ka electron kūpono o β-Ga2O3 ma ke ʻano he 0.28–0.33 me a me kona conductivity uila maikaʻi. Eia nō naʻe, hōʻike ka palena kiʻekiʻe o ka hui valence i kahi piʻo Ek pāpaʻu me ka curvature haʻahaʻa loa a me nā orbitals O2p kūloko ikaika, e hōʻike ana ua kūloko hohonu nā lua. Ke hōʻike nei kēia mau ʻano i kahi pilikia nui e hoʻokō i ka doping ʻano-p ma β-Ga2O3. ʻOiai inā hiki ke hoʻokō ʻia ka doping ʻano-P, noho ka lua μ ma kahi haʻahaʻa loa. 2. Ka ulu ʻana o ka kristal hoʻokahi gallium oxide nui A hiki i kēia manawa, ʻo ke ʻano ulu ʻana o ka substrate kristal hoʻokahi nui β-Ga2O3 ʻo ia ke ʻano huki kristal, e like me Czochralski (CZ), ke ʻano hānai ʻili lahilahi i wehewehe ʻia e ka ʻaoʻao (Edge -Defined film-fed, EFG), Bridgman (rtical a horizontal paha Bridgman, HB a i ʻole VB) a me ka ʻenehana ʻāpana lana (floating zone, FZ). Ma waena o nā ʻano hana āpau, manaʻo ʻia ʻo Czochralski a me nā ʻano hānai ʻili lahilahi i wehewehe ʻia e ka ʻaoʻao nā ala hoʻohiki nui loa no ka hana nui ʻana o nā wafers β-Ga 2O3 i ka wā e hiki mai ana, no ka mea hiki iā lākou ke hoʻokō i nā nui nui a me nā densities hemahema haʻahaʻa. A hiki i kēia manawa, ua hoʻomaopopo ka Novel Crystal Technology o Iapana i kahi matrix kalepa no ka ulu ʻana o ka heheʻe β-Ga2O3.
1.1 Ke ʻano hana Czochralski
ʻO ke kumumanaʻo o ke ʻano hana Czochralski, ʻo ia ka uhi mua ʻia ʻana o ka papa hua, a laila huki mālie ʻia ka kristal hoʻokahi mai ka heheʻe ʻana. Ke koʻikoʻi nei ke ʻano hana Czochralski no ka β-Ga2O3 ma muli o kona kumukūʻai kūpono, nā hiki ke nui, a me ka ulu ʻana o ka substrate kiʻekiʻe o ke kristal. Eia nō naʻe, ma muli o ke kaumaha wela i ka wā o ka ulu ʻana o Ga2O3 i ka mahana kiʻekiʻe, e ʻike ʻia ka mahu ʻana o nā kristal hoʻokahi, nā mea heheʻe, a me ka hōʻino ʻana i ka ipu hoʻoheheʻe Ir. ʻO kēia ka hopena o ka paʻakikī i ka hoʻokō ʻana i ka doping ʻano-n haʻahaʻa ma Ga2O3. ʻO ka hoʻokomo ʻana i ka nui kūpono o ka oxygen i loko o ka lewa ulu kekahi ala e hoʻoponopono ai i kēia pilikia. Ma o ka hoʻonui ʻana, ua ulu pono ʻia ka β-Ga2O3 2-ʻīniha kiʻekiʻe me kahi pae hoʻohuihui electron manuahi o 10^16~10^19 cm-3 a me ka nui o ka electron o 160 cm2/Vs e ke ʻano hana Czochralski.
Kiʻi 2. Ke aniani hoʻokahi o β-Ga2O3 i ulu ʻia e ke ʻano Czochralski
1.2 Ke ʻano hānai ʻana i ka ʻili i wehewehe ʻia
ʻO ke ʻano hānai ʻili lahilahi i wehewehe ʻia e ka lihi ka mea i manaʻo ʻia ʻo ia ke kumu nui no ka hana kalepa o nā mea kristal hoʻokahi Ga2O3 nui. ʻO ke kumumanaʻo o kēia ʻano hana, ʻo ia ke kau ʻana i ka heheʻe i loko o kahi ʻōmole me kahi ʻoki capillary, a piʻi ka heheʻe i ka ʻōmole ma o ka hana capillary. Ma luna, hana ʻia kahi ʻili lahilahi a pālahalaha i nā ʻaoʻao āpau me ka hoʻoulu ʻia e crystallize e ka kristal hua. Eia kekahi, hiki ke hoʻomalu ʻia nā kihi o ka ʻōmole luna e hana i nā kristal i loko o nā flakes, nā paipu, a i ʻole kekahi geometry i makemake ʻia. Hāʻawi ke ʻano hānai ʻili lahilahi i wehewehe ʻia e ka lihi o Ga2O3 i nā wikiwiki ulu wikiwiki a me nā diameters nui. Hōʻike ka Kiʻi 3 i kahi kiʻikuhi o kahi kristal hoʻokahi β-Ga2O3. Eia kekahi, ma ke ʻano o ka unahi nui, ua kūʻai ʻia nā substrates β-Ga2O3 2-ʻīniha a me 4-ʻīniha me ka transparency maikaʻi loa a me ke ʻano like, ʻoiai ua hōʻike ʻia ka substrate 6-ʻīniha i ka noiʻi no ke kūʻai aku ʻana i ka wā e hiki mai ana. I kēia manawa, ua loaʻa pū nā mea nui kristal hoʻokahi poepoe nui me ka orientation (−201). Eia kekahi, ʻo ke ʻano hānai ʻiliʻili i wehewehe ʻia e ka lihi β-Ga2O3 e paipai pū i ka doping o nā mea metala hoʻololi, e hiki ai ke noiʻi a me ka hoʻomākaukau ʻana o Ga2O3.
Kiʻi 3 β-Ga2O3 kristal hoʻokahi i ulu ʻia e ke ʻano hānai kiʻiʻoniʻoni i wehewehe ʻia e ka lihi
1.3 Ke ʻano hana Bridgeman
Ma ke ʻano Bridgeman, ua hoʻokumu ʻia nā kristal i loko o kahi ipu hoʻoheheʻe e neʻe mālie ʻia ma o kahi gradient mahana. Hiki ke hana ʻia ke kaʻina hana ma ke ʻano ākea a kū pololei paha, me ka hoʻohana pinepine ʻana i kahi ipu hoʻoheheʻe e wili ana. He mea kūpono ke hoʻomaopopo ʻana he hoʻohana paha kēia ʻano hana i nā hua kristal. ʻAʻole i ʻike pololei ʻia nā kaʻina hana hoʻoheheʻe a me ka ulu ʻana o ke kristal e nā mea hana Bridgman kuʻuna a pono e kāohi i nā mahana me ka pololei kiʻekiʻe. Hoʻohana nui ʻia ke ʻano Bridgman kū pololei no ka ulu ʻana o β-Ga2O3 a ua ʻike ʻia no kona hiki ke ulu i loko o kahi ea. I ka wā o ke kaʻina hana ulu ʻana o ke ʻano Bridgman kū pololei, ua mālama ʻia ka nalowale o ka nui o ka mea i hoʻoheheʻe ʻia a me ka ipu hoʻoheheʻe ma lalo o 1%, e hiki ai ke ulu o nā kristal hoʻokahi β-Ga2O3 nui me ka nalowale liʻiliʻi.
Kiʻi 4 Ke aniani hoʻokahi o β-Ga2O3 i ulu ʻia e ke ʻano Bridgeman
1.4 Ke ʻano hana ʻāpana lana
Hoʻoponopono ke ʻano hana lana wahi i ka pilikia o ka haumia kristal e nā mea ipu hao a hoʻemi i nā kumukūʻai kiʻekiʻe e pili ana me nā ipu hao infrared pale wela kiʻekiʻe. I loko o kēia kaʻina hana ulu, hiki ke hoʻomehana ʻia ka heheʻe e kahi kukui ma mua o kahi kumu RF, no laila e hoʻomaʻalahi ana i nā koi no nā lako ulu. ʻOiai ʻaʻole i kūpono loa ke ʻano a me ke ʻano kristal o β-Ga2O3 i ulu ʻia e ke ʻano hana lana wahi, wehe kēia ʻano hana i kahi ʻano hana hoʻohiki no ka ulu ʻana i ka β-Ga2O3 maʻemaʻe kiʻekiʻe i loko o nā kristal hoʻokahi kūpono i ke kālā.
Kiʻi 5 β-Ga2O3 kristal hoʻokahi i ulu ʻia e ke ʻano ʻāpana lana.
Ka manawa hoʻouna: Mei-30-2024