Ma semiconductor eWide bandgap (WBG) anomiririrwa nesilicon carbide (SiC) uye gallium nitride (GaN) anyanya kutariswa. Vanhu vane tarisiro huru yekushandisa silicon carbide mumotokari dzemagetsi nemagrid emagetsi, pamwe nekushandisa gallium nitride mu fast charging. Mumakore achangopfuura, tsvakiridzo paGa2O3, AlN uye madhaimani materials yakaita kufambira mberi kukuru, zvichiita kuti ultra-wide bandgap semiconductor materials ive chinhu chinonyanya kutariswa. Pakati pawo, gallium oxide (Ga2O3) imhando ye ultra-wide bandgap semiconductor material ine band gap ye 4.8 eV, ine theoretical critical breakdown field strength yeinenge 8 MV cm-1, saturation velocity yeinenge 2E7cm s-1, uye high Baliga quality factor ye 3000, ichinyanya kutariswa mumunda we high voltage uye high frequency power electronics.
1. Hunhu hwezvinhu zveGallium oxide
Ga2O3 ine gap hombe yeband (4.8 eV), inotarisirwa kuwana simba rekudzivirira voltage rakakwirira uye simba rakakwirira, uye inogona kuva nemukana wekugadzirisa voltage rakakwirira pakudzivirira kwakaderera, zvichiita kuti ive chinhu chinonyanya kutariswa muongororo dziripo. Pamusoro pezvo, Ga2O3 haina kungova nezvinhu zvakanaka chete, asiwo inopa matekinoroji akasiyana-siyana anogadziriswa nyore nyore e-n-type doping, pamwe nekukura kwe substrate kwakaderera uye matekinoroji e epitaxy. Kusvika parizvino, zvikamu zvishanu zvakasiyana zvekristaro zvakawanikwa muGa2O3, zvinosanganisira corundum (α), monoclinic (β), defective spinel (γ), cubic (δ) uye orthorhombic (ɛ) phases. Kugadzikana kweThermodynamic, muhurongwa, γ, δ, α, ɛ, uye β. Zvakakosha kuziva kuti monoclinic β-Ga2O3 ndiyo yakagadzikana zvakanyanya, kunyanya pakupisa kwakanyanya, nepo zvimwe zvikamu zviri metastable pamusoro pekupisa kwemukamuri uye zvinowanzo shanduka kuita β phase pasi pemamiriro chaiwo ekupisa. Saka, kugadzirwa kwemidziyo ine β-Ga2O3 kwave chinhu chikuru chakanyanya kutariswa munyaya dzemagetsi emagetsi mumakore achangopfuura.
Tafura 1 Kuenzanisa kwezvimwe zvikamu zvezvinhu zve semiconductor
Maumbirwo ekristaro e monoclinicβ-Ga2O3 anoratidzwa muTafura 1. Maparamita ayo e lattice anosanganisira a = 12.21 Å, b = 3.04 Å, c = 5.8 Å, uye β = 103.8°. Sero reyuniti rine maatomu eGa(I) ane twisted tetrahedral coordination uye maatomu eGa(II) ane octahedral coordination. Kune marongero matatu akasiyana eatomu eokisijeni mu "twisted cubic" array, anosanganisira maatomu maviri eO(I) neO(II) akarongeka katatu uye atomu rimwe reO(III) rakabatana tetrahedral. Kubatanidzwa kwemarudzi maviri aya e tetrahedral coordination kunotungamira ku anisotropy yeβ-Ga2O3 ine hunhu hwakakosha mufizikisi, makemikari corrosion, optics uye electronics.
Mufananidzo 1. Dhiyagiramu yechimiro chekiriniki ye β-Ga2O3
Kubva pamaonero edzidziso yesimba remagetsi, kukosha kushoma kwebhendi remagetsi reβ-Ga2O3 kunobva pamamiriro esimba anoenderana ne4s0 hybrid orbit yeatomu reGa. Musiyano wesimba pakati pekukosha kushoma kwebhendi remagetsi nedanho resimba remagetsi (electron affinity energy) unoyerwa. i4 eV. Huremu hwemaelectron hunoshanda hweβ-Ga2O3 hunoyerwa se0.28–0.33 me uye conductivity yayo yakanaka yemagetsi. Zvisinei, valence band maximum inoratidza shallow Ek curve ine curvature yakaderera uye O2p orbitals dzakasimba, zvichiratidza kuti maburi acho akanyanya kudzika. Hunhu uhwu hunopa dambudziko guru rekuwana p-type doping muβ-Ga2O3. Kunyangwe kana P-type doping ichigona kuwanikwa, buri μ rinoramba riri padanho rakaderera kwazvo. 2. Kukura kwebulk gallium oxide single crystal Kusvika pari zvino, nzira yekukura ye β-Ga2O3 bulk single crystal substrate inonyanya kushandisa nzira ye crystal pulling, senge Czochralski (CZ), edge-defined thin film feeding method (Edge-Defined film-fed, EFG), Bridgman (rtical kana horizontal Bridgman, HB kana VB) uye floating zone (floating zone, FZ) technology. Pakati penzira dzese, Czochralski uye edge-defined thin-film feeding methods dzinotarisirwa kuva nzira dzinovimbisa dzekugadzira mawafers e β-Ga 2O3 akawanda mune ramangwana, sezvo dzichigona kuwana huwandu hwakawanda uye defect densities shoma panguva imwe chete. Kusvika pari zvino, Novel Crystal Technology yeJapan yakawana matrix yekutengeserana yekukura kwe melt β-Ga2O3.
1.1 Nzira yeCzochralski
Nheyo yenzira yeCzochralski ndeyekuti jira rembeu rinotanga ravharwa, uye kristaro imwe chete inobviswa zvishoma nezvishoma kubva mukunyunguduka. Nzira yeCzochralski iri kuramba ichikosha kune β-Ga2O3 nekuda kwekushanda kwayo zvakanaka, kugona kwayo kukura kwakakura, uye kukura kwesubstrate yemhando yepamusoro yekristaro. Zvisinei, nekuda kwekumanikidzwa kwekupisa panguva yekukura kweGa2O3 pakupisa kwakanyanya, kupwa kwekristaro imwe chete, zvinhu zvinonyunguduka, uye kukuvara kweIr crucible zvichaitika. Izvi zvinokonzerwa nekuoma kwekuwana doping yakaderera yemhando yen muGa2O3. Kuisa huwandu hwakakodzera hweokisijeni mumhepo yekukura inzira imwe yekugadzirisa dambudziko iri. Kuburikidza nekugadzirisa, 2-inch β-Ga2O3 yemhando yepamusoro ine huwandu hwemaerekitironi akasununguka hwe10^16~10^19 cm-3 uye huwandu hwemaerekitironi hwakanyanya hwe160 cm2/Vs hwakakura zvinobudirira nenzira yeCzochralski.
Mufananidzo 2. Kiristaro imwe chete yeβ-Ga2O3 yakakurirwa nenzira yeCzochralski
1.2 Nzira yekudyisa firimu yakatsanangurwa nemucheto
Nzira yekudyisa zvidimbu zvitete zvakatsanangurwa mumucheto inoonekwa senzira inotungamira mukugadzirwa kwezvinhu zveGa2O3 single crystal materials munzvimbo yakakura. Nheyo yeiyi nzira ndeyekuisa kunyunguduka muchimiro chine kapillary slit, uye kunyunguduka kunokwira kuchimiro kuburikidza ne capillary action. Pamusoro, firimu rakatetepa rinoumbwa uye rinopararira kumativi ese uku richikurudzirwa kuti riite crystal ne seed crystal. Pamusoro pezvo, mipendero yekumusoro kwechimiro inogona kudzorwa kugadzira makristaro mumaflakes, machubhu, kana chero geometry inodiwa. Nzira yekudyisa zvidimbu zvitete zvakatsanangurwa mumucheto yeGa2O3 inopa kukurumidza kukura uye dhayamita hombe. Mufananidzo 3 unoratidza dhayagiramu yekristaro imwe chete yeβ-Ga2O3. Pamusoro pezvo, maererano nehukuru, zvidimbu zve 2-inch ne 4-inch β-Ga2O3 zvine kujeka kwakanaka uye zvakafanana zvakatengeswa, nepo substrate ye 6-inch ichiratidzwa mukutsvagisa kwekushambadzira mune ramangwana. Munguva pfupi yapfuura, zvinhu zvakakura zvedenderedzwa zvekristaro imwe chete zvave kuwanikwawo ne (−201) orientation. Pamusoro pezvo, nzira yekudyisa firimu yeβ-Ga2O3 inotsanangurirwa pamucheto inokurudzirawo kushandisa mishonga inodhaka yezvinhu zvesimbi zvinoshanduka, zvichiita kuti tsvakiridzo nekugadzirira Ga2O3 zvikwanisike.
Mufananidzo 3 β-Ga2O3 kristaro imwe chete inorimwa nenzira yekudyisa firimu yakatsanangurwa nemupendero
1.3 Nzira yeBridgeman
Munzira yeBridgeman, makristaro anoumbwa muchikamu chinopfurwa zvishoma nezvishoma kuburikidza netembiricha. Maitiro acho anogona kuitwa nenzira yakatwasuka kana yakatwasuka, kazhinji uchishandisa chinopfurwa chinotenderera. Zvakakosha kuziva kuti nzira iyi ingangoshandisa kana kusashandisa mbeu dzekristaro. Vashandi veBridgman vekare havaoni zvakananga maitiro ekunyunguduka uye kukura kwekristaro uye vanofanirwa kudzora tembiricha nemazvo. Nzira yeBridgman yakatwasuka inonyanya kushandiswa pakukura kweβ-Ga2O3 uye inozivikanwa nekukwanisa kwayo kukura munzvimbo yemhepo. Munguva yekukura kwenzira yeBridgman yakatwasuka, kurasikirwa kwese kwehuwandu hwemelt necrucible kunochengetwa pasi pe1%, zvichiita kuti kukura kwekristaro imwe chete yeβ-Ga2O3 yakakura nekurasikirwa kushoma.
Mufananidzo 4. Kristaro imwe chete yeβ-Ga2O3 inorimwa nenzira yeBridgeman
1.4 Nzira yenzvimbo inoyangarara
Nzira yefloating zone inogadzirisa dambudziko rekusvibiswa kwekristaro nezvinhu zvinopfurwa uye inoderedza mitengo yakakwira inokonzerwa neinfrared crucibles inodzivirira kupisa kwakanyanya. Munguva yekukura uku, kunyunguduka kunogona kupiswa nerambi kwete neRF source, zvichiita kuti zvinodiwa pakugadzira michina zvinorerutswa. Kunyangwe chimiro uye mhando yekristaro yeβ-Ga2O3 inorimwa nenzira yefloating zone zvisati zvanyatsonaka, nzira iyi inovhura nzira inovimbisa yekukura β-Ga2O3 yakachena kwazvo kuita makristaro madiki asingadhuri.
Mufananidzo 5 β-Ga2O3 kristaro imwe chete inorimwa nenzira yekuyangarara.
Nguva yekutumira: Chivabvu-30-2024